Honestly I've listened to so much shit from across the fucking map (in terms of geography, genre, era, etc.) that I don't really parse what I listen to as weird anymore. What other people may be confused or perturbed by is usually pretty understandable for me.
That being said, here's some stuff that I'm pretty sure people here would classify as "weird":
Gaber. I have no other words for this song but straight up retarded and disgusting. The chorus literary means: 'I'm not gay, but DJ, f*** me in the head.' Like what the actual hell? (I can translate the rest of the song but I'd rather not.)
I don't even need to stop and think; it's "Bohemian Rhapsody", hands down. That should be near the top of anyone's list. For those who aren't sure what that is, you may still recognize the first few lyrics: "Is this the real life?/Is this just fantasy/caught in a landslide/no escape from reality?"
While I haven't seen The Rocky Horror Picture Show, what little I've heard of the musical numbers tells me those are pretty strange, too.