<ul><li><a href="http://cgi.ebay.com/Wireless-Flash-Trigger-V2s-for-Canon-580EX-430EX-420EX_W0QQitemZ160205923060QQihZ006QQcategoryZ3008 6QQssPageNameZWDVWQQrdZ1QQcmdZViewItem">Linky</a></li></ul>

<ul><li><a href="http://www.gadgetinfinity.com/product.php?productid=16766">http://www.gadgetinfinity.com/product.php?productid=16766</a</li></ul>

If I had a real pro need, I'd have had the PW already.

then you'd have two light sources (or just one - 550ex can act as master without firing)

.. you should get some of these optical slaves if you have multiple flash youd like to use with the ebay triggers (without needing multiple receivers)

works great indoors and doesnt require any batteries.

http://flashzebra.com/opticalslaves/0050.shtml

2 Sunpak 383s and various softboxes and stands. This wireless unit is so I can use my 430EX with them, everything off-camera. I got the 430EX for backup wedding work and thought rather than buy another 383 (or SB-24/26, etc), use what I have a little better. I still may get another 383 for better background illumination, but I really haven't been able to test a 3-light setup yet to see if I'll need the fourth.