Canon Wireless

What are the options for Canon wireless flash.a I have a 400D with a Jessops flash. I saw someone at a concert with the same establishment, except they had a wireless transmitter so they can keep the flash gun at arm's length to get better shadows etc. But I can not seem to find one. If there is a cheaper alternative to a gun that would be nice! ;) I think the Canon STE2 you hol...