Since I scratched the sensor on my 400d, and then looked at getting the sensor replaced. It has made the ummm- aww decision of upgrading an awful lot easier. since the cost of a sensor replacement is steep enough that I would rather put towards an upgraded body since photography has become 'my thing'. The Canon 50d is looking the most likely target coupled with a 18-200mm ef-s lense to replace my aging secondhand 28-135 EF walkabout.
Camera Price Buster has proved useful in making sure that if I wander into Jessops (most likely option) that I won't be getting too fleeced for preferring the High Street. The site is a UK camera bits price comparison site, and updates daily. It also keeps a log of coupons which you can use to get money off on certain deals.
Not essential certainly but damned handy, and its noce to see this kind of site specifically for the UK:)