I just learned that Raymond Smullyan, a great mathematician with a passion for (among other things) mathematical and logical puzzles, has died on the 6th, at the ripe old age of 97. Here's an obituary from the NY Times.
I had two of his books when I was little (still do, in fact), Alice in Puzzle-Land and Satan, Cantor and Infinity. They're great books, and perhaps I should take this as a cue to read some of the rest of his works as well.
If you'd like a taste of his logic puzzles, the NY Times has a few samples here. (One hint: in the last puzzle, "either ... or" does not actually mean that; it's possible both the "either" and the "or" are correct.)