The 2011 CiSRA Puzzle Competition happened last week. Teams were limited to four people or fewer, which meant that several of our usual Plugh crew had to splinter off and form Xyzzy, a second team.
It went... well.
If you missed the competition but are interested in trying some of the puzzles, here're my recommendations (most links go to PDFs):
Art Heist: Brilliant idea, well-executed. I had to laugh at the absurdity of including the Mondrian. If you click one link in this post, make it this one. (Be warned, though - the final step may be significantly harder if you aren't Australian or have Australian friends to look at your results.)
Togetherness: One of my favorite moments from this year's competition was making a cheesy joke about this puzzle to my teammates, and then ten seconds later discovering that it was exactly the cheesy joke the constructor was going for. Maybe the best argument I've yet seen in favor of metas that allow for whatever answer the constructor needs.
Puzzle Competition Reminder: A puzzle that's about a second, intentionally awful puzzle. Only you never see the bad puzzle - you only see the series of emails in which the constructor and editor refine it, giving you just enough information to reconstruct it. Fun!
Latin Pipes II: Actually, I ought to recommend its slightly easier cousin Latin Pipes from last year instead - I've been hacking away at this one off and on for about a week now, and still haven't finished it. (Thankfully we had motris on hand for this during the actual competition.) It's an (as far as I know) original type of logic puzzle of the sort that makes puzzle authors (or at least me) go, "Why didn't I think of that?"
The Metapuzzle: I'm impressed at the amount of work that must have gone into writing the meta this year - it's essentially its own smaller-scale Hunt, a set of twenty mini-puzzle unlocked by solving the regular ones.