stopping wheel theft?
 

I guess the most obvious way to stop wheel theft is to actually loop a cable or chain lock through both tires and locked to the frame and/or the bike rack.

The other way, but not so easy, is to replace the quick release w/ the screw & nuts.

I just recently learned that one can use a hose clamp to prevent the quick release from working unless a thief is properly equipped w/ the right tools.

What other ways can be done to prevent wheel theft?

Use security skewers. The best are supposed to be Pitlocks (German and expensive) but others require use of a hex key or a similar 5 sided key. On Guard also makes a set of security skewers that use a proprietary design tool to tighten and loosen.

I replace the quick release with a standard bolt. In "safe" neighborhoods where I am sitting near my bike, I have a cable lock attaching the front wheel to the frame and a u-lock around the rear wheel and a locking post. If the bike will be out of my sight, or if I'm going downtown, I have a heavy u-lock around the rear wheel and a ultra-light u-lock attaching the front wheel to the frame.