I came across some interesting articles on the use of speedlight flashes. Both the following links are a by the same photographer, and while he uses a Nikon, there is little difference between that and using Canon equipment.
The use of speelight flashes for some off-camera light is fantastic, the only thing I am stuck on is where to get a warming gel to give the flash a wamer colour. I can’t seem to find any – does anyone know where I can get some in the UK? (or should I just use orange cellophane, or will that melt on to the front of the flash?)