A nice way to keep up is to try your hand at one of the countless online competitions. When looking some of these sites up for possible use in the classroom, I was pleased with http://ace.delos.com/usacogate , the trainingsite for the USA Computing Olympiad. Don't be deceived by the somewhat amateuristic look of the site and the abundance of cows. Once registered you can test your skills in algorithm programming on a large number of exercises ranging from easy to very difficult. Your solutions can be submitted and are automatically tested against a number of testcases. If you get it right the first time you get a nice compliment, but that only happened to me once :-)
Another link a got mentioned by Jos Bredek is http://www.hackquest.com. This site's layout also doesn't impress but the content seems ok. There you can take on 100 puzzles of 'hacking' yourself into webpages with unsecure Java applets, Javascript, etc. Jos has solved 30+ by now, a student already has 97!
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