[JCharlton]

I've become a big fan of round urethane belting. It's light, cheap, and easy to make the length you need. That length can be designed so you slip instead of stalling the motors, which believe me, is a good thing.

The only disadvantage is finding the pulleys, but if you have a lathe you can easily make your own.

Another cool trick is making a "quarter-drive", two shafts at 90 degrees separated by a couple of inches or more. We used this is 2009 and it worked great on our ball-conveyor (the "series of tubes").