
Have you seen the movie Brazil? If not, I highly recommend it. It's one of Terry Gilliam's finest movies. It features several unexpected cameos by Robert DiNero as a rouge heater mechanic (that's the best way I can describe it).
If you've seen the film you know it features many "pipes". Pipes seem to be one of Gilliam's themes. Shortly after DiNero appears on screen, he is examining a pipe and comments:
Now that's a pipe of a different color.
He says it so quietly it's almost hard to hear (I have to rewind the DVR several times to confirm). But sure enough, it's an Oz reference.
p.s. The cover of this film used to freak me out when I was younger.