Last February the 2008 Winter Scripting Games really gave me the push that I needed from dabbling with PowerShell to really getting up to speed and putting it to good use. Back then I put up a load of posts with all my solutions and other stuff related to the games. It's great to see that they are back for 2009. I'll be trying to find the time to complete all of the beginner and advanced challenges in PowerShell and posting explanation of the solutions here.
I'd recommend that anyone who is interested in scripting takes part. Start off by taking a look at all the introductory information, then have a look at Event 1. You'll need to download the competitor's pack which contains the resources for all the events. You might want to check out the Scripting Games forum and if you're on Twitter, you can get news about the games by following the Scripting Guys.