Equally impressive: http://d.hatena.ne.jp/ku-ma-me/20090916
A Ruby -> Python -> Perl -> Lua -> OCaml -> Haskell -> C -> Java -> Brainfuck -> Whitespace -> Unlambda -> Ruby quine!
A Ruby -> Python -> Perl -> Lua -> OCaml -> Haskell -> C -> Java -> Brainfuck -> Whitespace -> Unlambda -> Ruby quine!