Can we have patients prepay their deductible or copay to give the patients an incentive to show up or at least cancel an appointment rather than no-show?

I have never heard of practices requiring a prepay. You can certainly ask your payers if they would allow this; this is entirely up to them and their contract with you.

Some practices do charge no-show patients a fee, of course - usually around $15 to $25.

If you go this route, make sure you let patients know in advance (or it doesn't serve its purpose), and don't spend more time collecting it than it is worth. 

Reminder calls also work wonders.