Nate Trier has a blog on topics in improvisation and composition that you should definitely visit. I was just there and found that he has two recordings of improv games from my book Improv Games for One Musician (GIA, 2009, 50 p.). The first game is a duet (2:39) for sax (David Elkin-Ginnetti) and some kind of keyboard sound (Nate); titled Atonal Interval Warm-Up, where the performers are limited to certain intervals. Here they chose M7/m7, #4, M/m2nds.
In the second example (3:33) they did the interval game again, but this time used an ABA form:
A: 7ths, tritones
B: Perfect 4ths and 5ths
A: 7ths and tritones again
Thanks, guys, for trying the games and posting the recording of the results.
If any of you out there do the same, let me know, and I will (most likely) post the results here (or link to them).