I have little patience for bad movies in general but there are a few I really love. Here's my list, including some echos from several pages back:
Barbarella: Queen of the Galaxy (I've studied this film in an academic context! Fascinating)
Crank
Crank: High Voltage (this + above have the best premise for an action movie ever: if he stops doing exciting things, he DIES)
Cannibal Holocaust (warning for rape and animal dismemberment on camera, they are not fucking around)
Evil Dead I
Evil Dead II
Army of Darkness (confirmed for actual middle-aged man)
I have watched Silent Night, Deadly Night 2 all the way through. I'm not sure if I can say it's one of my favorites.
I watched The Room once with a large group not knowing that it had callouts and audience participation and everything. I was not prepared. I was a little overwhelmed. And my freshman buddies asked me to buy Scotch and vodka so they could make Scotchka. I got them the very best handles $30 could buy. Some of them had never tasted alcohol before. They were not prepared, either.