Wow. I'll second GHOSTS OF HANLEY HOUSE.

It took me about a week to make it through HANLEY HOUSE the first time (I kept falling asleep). Maybe it was that rewind-and-start-over, or rewind-to-the-last-part-I-remember, that ingratiated it into my subconscious. Whatever, I now watch it every few months. I even "upgraded" from my Sinister Cinema tape to Alpha's DVD. More of a lateral move than an upgrade. It's not a good movie, but it's earnest, and does have a certain creepiness to it. Especially when you're zoning in and out of sleep.

DUNGEON OF HARROW, THE THREE STOOGES IN ORBIT and SHRIEK OF THE MUTILATED fall into this inexplicable category, too.