YeoPhotoGroup by Keith Robins

Fifty foot flashgun trigger for less than twenty quid including postage from Hong Kong. Absolutely the best gadget for using an off camera flash ever!!! I've just sent off for a second one so I can fire two flashes without having to resort to a mini slave unit, which don't always work 100% when working near sunlight.
Ebay has plenty of these triggers listed, just make sure it is a radio trigger and not infra red operation as these can cause problems outdoors. Go to :- John Camera Shop
You get two AAA batteries with each trigger but they don't last long (about 500 operations before they're flat - you'll notice this when the working distance starts dropping dramatically) Duracells should last for several thousand flashes. There's a fairly rare battery in the transmitter but Googling in the details finds a replacement without a problem.
After using this for a few months and finding that the working limit really is about fifty metres I took a soldering iron to the reciever, added a mono mini jack socket, made up a 5 metres lead and can now use the transmitter to fire my camera from over a hundred feet (useful for birds / wild animals / motorsports etc).
The first press focuses the camera and the second press fires the shutter. Am having great fun with this setup as you can see by my self portraits.
Inside the top of the reciever are two wires connected to the hotshoe. I joined both of these to either side of the mini jack socket and can now use still use it for either flash or camera, obviously not both at the same time or your flash will go off before the shutter is fully open. I've not set this up alongside a speed camera, yet, but you could have some fun and maybe save a life by giving it a whirl.
You'll have noticed that the hotshoe only has two contacts so it works my Vivitar 285HV no problem. Those of you with a Cannon 580 / 430 or a Nikon type flash would have better results by slipping in a piece of plastic from a sandwich or cake casing available from your supermarket, or use a section of milk carton. Cut out a tiny square with a hole in the centre for the middle contact of your ETTL / TTL flash, into the hotshoe before fitting in the gun.
I'm guessing that you are by now beginning to get the hang of using your flash and camera both in manual mode as us strobists do, if not I will be posting up how you can learn this fascinating technique soon as time permits.