Mark's #29: Land Unter
But enough people said nice things about it (hi, Invisible Craig!) to convince me to try it again while I had some brain cells working - and it's slowly but surely risen up my favorites list. I esp. like the "duplicate" element to the game.
Theme is not really a big deal here - the original edition was about cuckoos stealing eggs. The edition I own (Berliner Spielkarten) has drowning pigs and a maniacal weather frog (armed with some kind of wand). Don't sweat the theme... it's a great game.