new file mode 100644
--- /dev/null
+++ b/runtime/syntax/plaintex.vim
@@ -0,0 +1,166 @@
+" Vim syntax file
+" Language:         TeX (plain.tex format)
+" Maintainer:       Nikolai Weibull <now@bitwi.se>
+" Latest Revision:  2006-03-26
+
+if exists("b:current_syntax")
+  finish
+endif
+
+let s:cpo_save = &cpo
+set cpo&vim
+
+syn match   plaintexControlSequence         display contains=@NoSpell
+      \ '\\[a-zA-Z@]\+'
+
+runtime! syntax/coretex.vim
+
+syn match   plaintexComment                 display
+      \ contains=ALLBUT,coretexComment,plaintexComment
+      \ '^\s*%[CDM].*$'
+
+if exists("g:plaintex_delimiters")
+  syn match   plaintexDelimiter             display '[][{}]'
+endif
+
+syn match   plaintexRepeat                  display contains=@NoSpell
+      \ '\\\%(loop\|repeat\)\>'
+
+syn match   plaintexCommand                 display contains=@NoSpell
+      \ '\\\%(plainoutput\|TeX\)\>'
+syn match   plaintexBoxCommand              display contains=@NoSpell
+      \ '\\\%(null\|strut\)\>'
+syn match   plaintexCharacterCommand        display contains=@NoSpell
+      \ /\\\%(["#$%&'.=^_`~]\|``\|''\|-\{2,3}\|[?!]`\|^^L\|\~\|\%(a[ae]\|A[AE]\|acute\|[cdHoOPStuvijlL]\|copyright\|d\=dag\|folio\|ldotp\|[lr]q\|oe\|OE\|slash\|ss\|underbar\)\>\)/
+syn match   plaintexDebuggingCommand        display contains=@NoSpell
+      \ '\\\%(showhyphens\|tracingall\|wlog\)\>'
+syn match   plaintexFontsCommand            display contains=@NoSpell
+      \ '\\\%(bf\|\%(five\|seven\)\%(bf\|i\|rm\|sy\)\|it\|oldstyle\|rm\|sl\|ten\%(bf\|ex\|it\=\|rm\|sl\|sy\|tt\)\|tt\)\>'
+syn match   plaintexGlueCommand             display contains=@NoSpell
+      \ '\\\%(\%(big\|en\|med\|\%(no\|off\)interline\|small\)skip\|\%(center\|left\|right\)\=line\|\%(dot\|\%(left\|right\)arrow\)fill\|[hv]glue\|[lr]lap\|q\=quad\|space\|topglue\)\>'
+syn match   plaintexInsertsCommand          display contains=@NoSpell
+      \ '\\\%(\%(end\|top\)insert\|v\=footnote\)\>'
+syn match   plaintexJobCommand              display contains=@NoSpell
+      \ '\\\%(bye\|fmt\%(name\|version\)\)\>'
+syn match   plaintexInsertsCommand          display contains=@NoSpell
+      \ '\\\%(mid\|page\)insert\>'
+syn match   plaintexKernCommand             display contains=@NoSpell
+      \ '\\\%(en\|\%(neg\)\=thin\)space\>'
+syn match   plaintexMacroCommand            display contains=@NoSpell
+      \ '\\\%(active\|[be]group\|empty\)\>'
+syn match   plaintexPageCommand             display contains=@NoSpell
+      \ '\\\%(\%(super\)\=eject\|nopagenumbers\|\%(normal\|ragged\)bottom\)\>'
+syn match   plaintexParagraphCommand        display contains=@NoSpell
+      \ '\\\%(endgraf\|\%(non\)\=frenchspacing\|hang\|item\%(item\)\=\|narrower\|normalbaselines\|obey\%(lines\|spaces\)\|openup\|proclaim\|\%(tt\)\=raggedright\|textindent\)\>'
+syn match   plaintexPenaltiesCommand        display contains=@NoSpell
+      \ '\\\%(allow\|big\|fil\|good\|med\|no\|small\)\=break\>'
+syn match   plaintexRegistersCommand        display contains=@NoSpell
+      \ '\\\%(advancepageno\|new\%(box\|count\|dimen\|fam\|help\|if\|insert\|language\|muskip\|read\|skip\|toks\|write\)\)\>'
+syn match   plaintexTablesCommand           display contains=@NoSpell
+      \ '&\|\\+\|\\\%(cleartabs\|endline\|hidewidth\|ialign\|multispan\|settabs\|tabalign\)\>'
+
+syn region  plaintexMath                    matchgroup=plaintexMath
+      \ contains=@plaintexMath
+      \ start='\$' skip='\\\\\|\\\$' end='\$'
+syn region  plaintexMath                    matchgroup=plaintexMath
+      \ contains=@plaintexMath keepend
+      \ start='\$\$' skip='\\\\\|\\\$' end='\$\$'
+
+syn cluster plaintexMath
+      \ contains=plaintexMathCommand,plaintexMathBoxCommand,
+      \ plaintexMathCharacterCommand,plaintexMathDelimiter,
+      \ plaintexMathFontsCommand,plaintexMathLetter,plaintexMathSymbol,
+      \ plaintexMathFunction,plaintexMathOperator,plaintexMathPunctuation,
+      \ plaintexMathRelation
+
+syn match   plaintexMathCommand             display contains=@NoSpell contained
+      \ '\\\%([!*,;>{}|_^]\|\%([aA]rrowvert\|[bB]ig\%(g[lmr]\=\|r\)\=\|\%(border\|p\)\=matrix\|displaylines\|\%(down\|up\)bracefill\|eqalign\%(no\)\|leqalignno\|[lr]moustache\|mathpalette\|root\|s[bp]\|skew\|sqrt\)\>\)'
+syn match   plaintexMathBoxCommand          display contains=@NoSpell contained
+      \ '\\\%([hv]\=phantom\|mathstrut\|smash\)\>'
+syn match   plaintexMathCharacterCommand    display contains=@NoSpell contained
+      \ '\\\%(b\|bar\|breve\|check\|d\=dots\=\|grave\|hat\|[lv]dots\|tilde\|vec\|wide\%(hat\|tilde\)\)\>'
+syn match   plaintexMathDelimiter           display contains=@NoSpell contained
+      \ '\\\%(brace\%(vert\)\=\|brack\|cases\|choose\|[lr]\%(angle\|brace\|brack\|ceil\|floor\|group\)\|over\%(brace\|\%(left\|right\)arrow\)\|underbrace\)\>'
+syn match   plaintexMathFontsCommand        display contains=@NoSpell contained
+      \ '\\\%(\%(bf\|it\|sl\|tt\)fam\|cal\|mit\)\>'
+syn match   plaintexMathLetter              display contains=@NoSpell contained
+      \ '\\\%(aleph\|alpha\|beta\|chi\|[dD]elta\|ell\|epsilon\|eta\|[gG]amma\|[ij]math\|iota\|kappa\|[lL]ambda\|[mn]u\|[oO]mega\|[pP][hs]\=i\|rho\|[sS]igma\|tau\|[tT]heta\|[uU]psilon\|var\%(epsilon\|ph\=i\|rho\|sigma\|theta\)\|[xX]i\|zeta\)\>'
+syn match   plaintexMathSymbol              display contains=@NoSpell contained
+      \ '\\\%(angle\|backslash\|bot\|clubsuit\|emptyset\|epsilon\|exists\|flat\|forall\|hbar\|heartsuit\|Im\|infty\|int\|lnot\|nabla\|natural\|neg\|pmod\|prime\|Re\|sharp\|smallint\|spadesuit\|surd\|top\|triangle\%(left\|right\)\=\|vdash\|wp\)\>'
+syn match   plaintexMathFunction            display contains=@NoSpell contained
+      \ '\\\%(arc\%(cos\|sin\|tan\)\|arg\|\%(cos\|sin\|tan\)h\=\|coth\=\|csc\|de[gt]\|dim\|exp\|gcd\|hom\|inf\|ker\|lo\=g\|lim\%(inf\|sup\)\=\|ln\|max\|min\|Pr\|sec\|sup\)\>'
+syn match   plaintexMathOperator            display contains=@NoSpell contained
+      \ '\\\%(amalg\|ast\|big\%(c[au]p\|circ\|o\%(dot\|plus\|times\|sqcup\)\|triangle\%(down\|up\)\|uplus\|vee\|wedge\|bmod\|bullet\)\|c[au]p\|cdot[ps]\=\|circ\|coprod\|d\=dagger\|diamond\%(suit\)\=\|div\|land\|lor\|mp\|o\%(dot\|int\|minus\|plus\|slash\|times\)pm\|prod\|setminus\|sqc[au]p\|sqsu[bp]seteq\|star\|su[bp]set\%(eq\)\=\|sum\|times\|uplus\|vee\|wedge\|wr\)\>'
+syn match   plaintexMathPunctuation         display contains=@NoSpell contained
+      \ '\\\%(colon\)\>'
+syn match   plaintexMathRelation            display contains=@NoSpell contained
+      \ '\\\%(approx\|asymp\|bowtie\|buildrel\|cong\|dashv\|doteq\|[dD]ownarrow\|equiv\|frown\|geq\=\|gets\|gg\|hook\%(left\|right\)arrow\|iff\|in\|leq\=\|[lL]eftarrow\|\%(left\|right\)harpoon\%(down\|up\)\|[lL]eftrightarrow\|ll\|[lL]ongleftrightarrow\|longmapsto\|[lL]ongrightarrow\|mapsto\|mid\|models\|[ns][ew]arrow\|neq\=\|ni\|not\%(in\)\=\|owns\|parallel\|perp\|prec\%(eq\)\=\|propto\|[rR]ightarrow\|rightleftharpoons\|sim\%(eq\)\=\|smile\|succ\%(eq\)\=\|to\|[uU]parrow\|[uU]pdownarrow\|[vV]ert\)\>'
+
+syn match   plaintexParameterDimen          display contains=@NoSpell
+      \ '\\maxdimen\>'
+syn match   plaintexMathParameterDimen      display contains=@NoSpell
+      \ '\\jot\>'
+syn match   plaintexParagraphParameterGlue  display contains=@NoSpell
+      \ '\\\%(\%(big\|med\|small\)skipamount\|normalbaselineskip\|normallineskip\%(limit\)\=\)\>'
+
+syn match   plaintexFontParameterInteger    display contains=@NoSpell
+      \ '\\magstep\%(half\)\=\>'
+syn match   plaintexJobParameterInteger     display contains=@NoSpell
+      \ '\\magnification\>'
+syn match   plaintexPageParameterInteger    display contains=@NoSpell
+      \ '\\pageno\>'
+
+syn match   plaintexPageParameterToken      display contains=@NoSpell
+      \ '\\\%(foot\|head\)line\>'
+
+hi def link plaintexOperator                Operator
+
+hi def link plaintexDelimiter               Delimiter
+
+hi def link plaintexControlSequence         Identifier
+hi def link plaintexComment                 Comment
+hi def link plaintexInclude                 Include
+hi def link plaintexRepeat                  Repeat
+
+hi def link plaintexCommand                 coretexCommand
+hi def link plaintexBoxCommand              plaintexCommand
+hi def link plaintexCharacterCommand        coretexCharacterCommand
+hi def link plaintexDebuggingCommand        coretexDebuggingCommand
+hi def link plaintexFontsCommand            coretexFontsCommand
+hi def link plaintexGlueCommand             plaintexCommand
+hi def link plaintexInsertsCommand          plaintexCommand
+hi def link plaintexJobCommand              coretexJobCommand
+hi def link plaintexKernCommand             plaintexCommand
+hi def link plaintexMacroCommand            coretexMacroCommand
+hi def link plaintexPageCommand             plaintexCommand
+hi def link plaintexParagraphCommand        plaintexCommand
+hi def link plaintexPenaltiesCommand        plaintexCommand
+hi def link plaintexRegistersCommand        plaintexCommand
+hi def link plaintexTablesCommand           plaintexCommand
+
+hi def link plaintexMath                    String
+hi def link plaintexMathCommand             plaintexCommand
+hi def link plaintexMathBoxCommand          plaintexBoxCommand
+hi def link plaintexMathCharacterCommand    plaintexCharacterCommand
+hi def link plaintexMathDelimiter           plaintexDelimiter
+hi def link plaintexMathFontsCommand        plaintexFontsCommand
+hi def link plaintexMathLetter              plaintexMathCharacterCommand
+hi def link plaintexMathSymbol              plaintexMathLetter
+hi def link plaintexMathFunction            Function
+hi def link plaintexMathOperator            plaintexOperator
+hi def link plaintexMathPunctuation         plaintexCharacterCommand
+hi def link plaintexMathRelation            plaintexOperator
+
+hi def link plaintexParameterDimen          coretexParameterDimen
+hi def link plaintexMathParameterDimen      coretexMathParameterDimen
+hi def link plaintexParagraphParameterGlue  coretexParagraphParameterGlue
+hi def link plaintexFontParameterInteger    coretexFontParameterInteger
+hi def link plaintexJobParameterInteger     coretexJobParameterInteger
+hi def link plaintexPageParameterInteger    coretexPageParameterInteger
+hi def link plaintexPageParameterToken      coretexParameterToken
+
+let b:current_syntax = "plaintex"
+
+let &cpo = s:cpo_save
+unlet s:cpo_save
+