There's a trick where you perform a regular cascade on the right side of your body with your left arm wrapped around your back, and left wrist pinned against your right side just above the hip. Transition from this cascade to the same trick on the left side gradually by way of a blind behind-the-back cascade. This looks very difficult but possible.
Ordinary right-hand single pass on the beat, *but* pass by carrying the club over your left hand, then hooking it around underneath so it comes spinning (normal pass spin) out from under your left forearm. I'm told it looks very stupid.
Noé has pointed out there's time for a right-hand self after any left double. Interesting combinations include: right-handed self shoulder throw followed by tomahawk; flourish; slide off the shoulder.
Noé and Ben said the Entropy people had been playing with the idea that any trick can be time-reversed; so e.g. a time-reversed 3-club cascade is a reverse cascade with reverse spins. I particularly like the reversed backcross; it seems pretty smooth done with a tennis pattern with just one club, though I haven't managed to work it into a three club pattern yet. It'd also be interesting to learn a number of tricks backwards and figure out how to flip direction quickly so as to make the time-reversal obvious. The entropy people claimed to have managed reversed versions of some of the more complicated passes.
I've been working on various crossed-arm body throws; e.g. under the left leg with the right hand, followed by catching the same ball under the right leg with the left hand, followed by a right-hand catch behind the back under the left arm, thrown from there to a symmetric left-hand catch on the right side. I think it's basically a shape-distorted Mill's Mess.
There's a trick where you use your right hand to place a club on your left shoulder, and let it slide down your back to a catch at your side with your left hand. An odd variation is to reach behind your neck with your right arm, place the club in *front* of your left shoulder, then catch with your left hand. I also wonder whether it's possible to slide it around a bent left leg in such a way that you can land it in place for a right-footed kickup.
As of spring 2005 I can now often get several runs in a row of 3 consecutive Alberts. (And as of early 2009--I can't say much more than that. So much for progress.)