For Nikon shooters out there (of which I am one - D200 with SB-800 flahses), you already have that option by using "Commander Mode", but because it is IR (infrared) it is predicated on line of site - if your camera trigger can't see the off camera flash, then it won't fire, no flash - no picture, and if you're shooting a wedding (or other live event) you most likely will not have a chance for a "do over".
Pocket Wizards are an option, but a very, very expensive option.
I recently bought (on eBay) a trigger/receiver set with an extra receiver from Gadget Infinity and with shipping it all came to just over $60. They ship from Hong Kong but much to my surprise these bad boys were knocking on my door in just 6 days (that's right, from order to delivery was less than a week). From talking to others, this is the rule, NOT the exception. The quickest delivery has thus far been 5 days.
They even come with batteries so you can start flashing right out of the box. Though to be honest, they are not the greatest of batteries so do your self a favor and get some batteries to have at the ready. They take the CR2 type battery, which is not the cheapest in the world, but again, on eBay, I got 5 brand name (Energizer Lithium) batteries for $9, yes - that included delivery.
I love eBay!
These are 4 channel triggers and for some reason (mostly with Canon flashes) some channels are more reliable than others. Duncan Babbage has done us all a great service by extensively testing theses radio triggers and he can tell you which are the "God Channels". You can see his complete write-up and view the results of his testing here. So far (here the sound of knocking on wood) I have not had a single missfire.
If you have read this far and are still wondering why you might want to take the flash of your camera, go to Flash Flavor and view the stunning work of Matt Adcock and Sol Tamargo, work done with off camera flashes. Be sure to take the time and scroll (slowly) to the bottom of their page and see everything stunning image they have to offer.
For under $100 you can truly take your work to another level.
At this point I want to talk strictly to the Nikon shooters, so all you Canon folks return to your lives, there is nothing to see here.
If you own Nikon gear, you have to visit Nikonians.org, a great place with a ton of resources and references. If you want to see a great tutorial on hw to uses your flash, they have it, how about an in-depth look at Nikons Creative Lighting System (all that Commander Mode Stuff), product reviews, FAQ's, eBooks, and a library of information is at your finger tips at this website, so be sure to take advantage of it, 'cause it's all free.
That's it for this entry, I am off to shoot a wedding with Stacey Kane, have yourselves a great weekend.