Just been reminded that Project Honeynet resurrected their challenges. If you're a packet monkey or log hound like me they're well worth taking a look at. One of the best things about them are the explanations put up after a challenge has been won are informative, so even if you're not going to win any prizes you'll still get stuff out of it.
Oh and while I think about it, I learnt a big lesson on keeping your tools up to date this week. Trying to solve a puzzle with out of date tools = annoying. Realising every machine you were solving it from had the right version when you were ssh into a box with the wrong one = massive rage.