If there's a penalty, that's news to me. As I recall, there were commissions, then a lot of complaints, then they dropped commissions. I mostly stopped PPX trading after amassing about a million dollars. It's not about playing the market now, it's actually about making a prediction and sticking with it to the end.
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Science is reinventing play, from extreme sports to gamification to ridiculous roller coasters to the playgrounds of tomorrow, and this issue is chock full of fun. Also, on a less fun note: Did global warming destroy my hometown?