(individually) disturbing/transcendent movie experiences

'Weekend of Fear' festival 1988(?), last movie @4 in the morning was The Act of Seeing with One's Own Eyes by Stan Brakhage, USA 1971.
The film itself is actually a filmed autopsy in b/w, but in a very forensic, scientific way. No mondo stuff.

Thing is, that its a silent picture. so there was this depressing silence in this big cinema with ~50 viewers. A very present silence, like the known 500lbs gorilla. After 10 minutes the projectionist chose to play some reggae/dub from a tape, maybe to 'loosen the tension'
First only a few ppl started laughing, but it was very infectious and the laughter spreaded rapidly over most of the overtired bunch. The laughter grew & grew and turned into hysteric howls.

oh, and there was this night with a bottle jack daniels & The Tenant by Polanski.