Cyan, Inc., the company that gave us the wonderfully whimsical Cosmic Osmo (which I played constantly as a child), Myst (which I owned but never played) and Riven (which I also never played), also gave us this odd little game in 1988:

This is actually not the original game; this is the CD-ROM Masterpiece Edition, which is the one I had as a kid. I remember enjoying this game quite a bit, but watching this playthrough, some of it actually looks kind of terrifying.