Every year I plug the US Puzzle Championship, which occurs on June 15th this year. You print out a pdf full of logic puzzles, solve them, and input the solutions online. Go register now! I need more competition.
This marks the ninth time I've participated. Persistence paid off, because last year was when I finally broke into the top 25. I got some sort of prize, but through a real-life comedy of errors, I haven't actually seen the prize yet (but I will soon!).