I like that idea a whole lot. I tend to just throw stuff on GitHub. Some is prototypal. Some is polished. Some is just terrible in every way. Your approach seems better, and is aptly named.

I can't take credit for it - the idea came from Andrew Tridgell - https://github.com/tridge/junkcode

http://samba.org/ftp/tridge/talks/junkcode.pdf%E2%80%8E

That's a pretty good idea, actually. Sometimes I throw a repo up to play, but take it down out of insecurity...