Love this. I did the first couple of days within irb (Ruby REPL) before deciding to actually write scripts, seeing the second exercise for a given day builds on the first. Found it interesting there's a "Leader board" since well, there's no "points" to accumulate other than completing two puzzles per day, so whomever is listed there is just those 100 who came to see the puzzles first. So far they're not very hard, but still fun.