Today I decided I wanted to get both 580EXII off camera further than an OC-E3 cable would allow - like 10 metres away from my camera... and I don't have a 10 metre OC-E3 cord.
So I tried some wireless wackiness. I grabbed my old Cactus triggers/receivers leftover from my pre-OC-E3 days. But, one receiver is a V2 and the other is a V2s. The V2s doesn't work with the 580EXII, so that was good for one flash... what about the other?
Easy! Set the 580EXII on the V2 as a master and have it trigger the other one as a slave - should work, right? (Of course, ETTL goes out the window. No problem for a strobist)
It seems there's a signal propogation delay meaning that I couldn't sync both flashes above about 1/60th of a second. Not a big deal for what I had in mind. The point is, it worked!
Strobism gives you wings...
... but it won't help you shave!