I got this phone as an upgrade but I don't really need a new one. Its completely unused and still has all the plastic screen/lens protectors attached. It is mainly targeted at those looking for a good camera on their phone, with 3.2 megapixels and a duel LED flash. It also has a feature called smile shutter which causes the picture to be automatically taken when the subject smiles, which is quite cool.
for more info see http://www.3g.co.uk/PR/Jan2009/Sony_Ericsson_Unveils_C510_Cyber_Shot_3G_Phone_3G.htm
This is locked to the 3 network so if you want to use it on another then it will need to be unlocked. I can include a 3 pay-as-you-go sim card with the phone if you'd like. Next best price listed on HUKDs is tesco mobile £105.
As I have no feedback I would be willing to post first IF the buyer has excellent feedback. Alternatively I could deliver or buyer could collect (and save on postage) if around the High Wycombe area. I would accept bank transfer, paypal gift, cheque or cash on collection.