I discovered these back in University. I don;t know what the hell I was searching for, but these are old as hell, and you'll probably want to turn the sound down.
Tranny or Granny
http://www2.b3ta.com/bigquiz/trannyorgranny/
Female or Shemale
http://www2.b3ta.com/bigquiz/femaleorshemale/
Funnel or Tunnel
http://www2.b3ta.com/bigquiz/funnelortunnel/
Gash or Tash
http://www2.b3ta.com/bigquiz/gash-or-tash/
Haxor or Spacker (my favorite)
http://www2.b3ta.com/bigquiz/hacker-or-spacker/
He-cat or She-cat
http://www2.b3ta.com/bigquiz/hecatorshecat/
Man milk or Moo milk
http://www2.b3ta.com/bigquiz/man-milk-or-moo-milk/
Enjoy...