LuaJIT 2.0 is an amazing achievement.  On the programming language shootout's "flawed benchmarks", LuaJIT outperforms almost every other dynamic language (including JavaScript V8, Python, Ruby 1.9, JRuby, VisualWorks Smalltalk, CPython, PLT Scheme), and is competetive on many benchmarks with highly-optimized language implementations like Sun's JVM, and GHC:<p><a href="http://shootout.alioth.debian.org/u32q/which-programming-languages-are-fastest.php?gpp=on&#38;java=on&#38;csharp=on&#38;ghc=on&#38;sbcl=on&#38;luajit=on&#38;hipe=on&#38;v8=on&#38;vw=on&#38;mzscheme=on&#38;lua=on&#38;python=on&#38;php=on&#38;perl=on&#38;ruby=on&#38;calc=chart" rel="nofollow">http://shootout.alioth.debian.org/u32q/which-programming-lan...</a><p>Mike Pall wrote LuaJIT and now LuaJIT 2 as essentially solo efforts.  Thanks to Google and the other sponsors for helping him continue!