If you're new to the radio trigger systems of photography, but are interested in learning more about them I would highly recommend checking out www.radiopopper.com. These nifty triggers allow you to use flashes off camera and at great distances. The radio popper system is roughly the same price as the Pocket Wizards are, but the company will be coming out with the Radio Popper Jr. From what I've read so far they are looking to be priced around 100$ for a trigger and receiver which would be a super price point. Until those are released though there are a lot of different options available that you could try out. I've listed some of them below for easy reference.

Wireless Shutter Release for Canon EOS 50D 40D 7D 1Ds    US $32.95

Wireless Shutter Release for Canon EOS 1000D 550D 60D    US $29.95

900W Strobe Studio Flash Light Kit For Bowens Accessories Photography Lighting    US $434.48

TT520 Speedlite Flash For Canon Nikon Sony Camera E4M    US $46.89

TT520 Flash Speedlite for Canon Rebel T2i XTi XS 550D    US $46.90