Remember when a studio could center an entire game around a living glove, and that wasn't questioned as irrational behavior? Yes, the days of Glover were simpler times. The game was set to receive a sequel, though that was eventually canceled. Now, an early version has become playable. No joke!
A Glover 2 prototype cartridge was acquired by NES World, and rather than have it sit on a shelf somewhere, unplayed and unloved, it's been uploaded to the Internet for anyone curious enough to find it.
Alternatively, you can save yourself the effort by watching this video. Unsurprisingly, the sequel looks rather dated and not particularly enjoyable -- even as someone who liked Glover a fair amount -- but what else would you expect? The novelty of it, however, is undeniable.
Unreleased Nintendo 64 Sequel To Glover Surfaces Online [Retro Collect via GameSetWatch]