Just a quickie to let you know I've used the Justgiving site as a way of online sponsorship. It's so easy to set up, takes about 10 minutes to get a page up and running, and it enables donors to give by credit card, saving the hassle of having to round up your sponsors after the big event.
For those interested in having a look at a page in action, check mine out at http://www.justgiving.com/marathonmadness
This isn't a plug to try and get sponsors (although I won't turn you away if you insist on sponsoring me!) but I thought I'd post this to try and help you charity runners out there.