The Null Device
In 2001, a chap by the name of Aaron Ardiri wrote a port of Lemmings to the PalmOS PDA platform. Now, he has given himself 36 hours to port it to two modern mobile platforms, the iPhone and Palm webOS, with OSX and Windows desktop ports for good measure. Ardiri posted his progress, and interim OSX binaries, to a liveblog here; it seems to be down, but there's a long, scroll-like screenshot of the whole thing here. It's quite interesting, in its descriptions of how coding practices have changed as platforms have become less cramped, and of the process of adapting 2001-vintage PalmOS code to larger (mostly UNIX-based) systems.
Ardiri is considering adding another port to Android; I imagine this would involve some means of translating ancient, low-level C code into Java (or else a C compiler that produces Dalvik bytecode). If he's just dealing in C-based platforms, he could add Nokia's various platforms and (from what I hear) Samsung's new "Bada" OS, though whether there'd be much reason to bother is an open question.