My favourites are the usual ones that people choose - State Of The Art and 9 fingers by Spaceballs, CyberCinemaTastic and The Castle by Loonies, Lapsuus by Mature Furk, Desert Dreams by Kefrens. I used to like Jesus on E's but I've gone off it recently...
I don't really like TBL demos - they're all a bit "samey" and have pretty poor performance on 060 when you compare to similar demos from other groups.... they spent too much time coding PC's I think to remember what optimisation is l)