Table Cameras
Sometimes couples choose to have disposable table cameras at the reception instead of (or in addition to) hiring a photographer. The idea is to get lots of candids without spending a lot of money.
If you decide to do this, be sure to get cameras that use good quality film that is NOT near or past its expiration date. It's much more important to have film that can be properly developed than it is to get a great deal on cute wedding cameras. (I've heard horror stories of people that spent a lot on developing only to get back photos that didn't look right, because the film was expired.) You also want to be sure to buy the right type of camera for the lighting conditions they'll be used under. (Consider the kind with built-in flash if you're having an evening reception.)
I actually think you're more likely to get nice candids from your wedding guests if you simply ask if you can get reprints from those who happened to bring their own cameras. (The reason being that if they brought their own cameras, chances are they're interested in photography and familiar with how to use them.)