On the topic of cassette DJing, if you haven't seen this you really should...
The Cassette Jockey World Championships:
http://www.post-data.org/cassette/
They only seemed to get as far as doing one in 2003.. dunno what happened to them after that.
From their FAQ:
"What are some of the techniques that competitors used last year?
-- To name a few, CJ Larry made some loop tapes from released recordings and rubbed off parts of
the tape to get different rhythms; CJ Yergy Yelevi removed a tape head from a tape deck, mounted it
on a pencil, and then "scratched" it back and forth over some suspended tape; CJ Howard Stelzer used
some hand-held cassette players with mics and speakers to generate feedback (while using only Billy
Joel tapes for source material); CJ LeDeuce used his four-track to play slow, ambient style washes
mixed with half-speed Lionel Richie; CJ Freakface dressed up in a clown suit, played lots of eurodance
hits, and pumped his fist (and came in third)."