Operation Logic BombOh yeah, that's an awesome game. It's not terribly long, about what you'd expect from an average arcade game, but it's loads of fun while it lasts.
Did anyone mention Holy Umbrella: Dondera's Wild!!? If not, then I am. Gid did a great job with that release.
EDIT: Of course, given that Gideon actually posted this topic, he'd already know about it and then some. Still, anyone that hasn't tried it should do so.