A bit of a no brainer really... :-)
Nikon D40 with voucher and cashback from Nikon until June this year.
Take off 5% for the voucher YAW744 and free delivery voucher AWSPRDEL and it works out at £265.99! Then with Nikon's cashback that makes it £235.99.
Also don't forget 3.5% Quidco available!
Cashback link here:http://www.nikon.co.uk/sites/cashback/spring2008_default.html
Voucher expired :(