This is my first proper deal post so be gentle!
I've been looking for a good HTC desire deal as three wanted to shaft me on an upgrade and found this which looks good, obviously if you can be bothered with the cashback hassle.
HTC desire brown on T-Mobile
£160 cashback by redemption in 5 stages (£32 pound a go)
£40 quidco cashback
works out to £18.89pm or £340.02 over the 18 month contract.
If you can't be bothered with the £160 cashback by redemption they also do a £80 instant cashback here....http://bit.ly/b9Aj3N
Its the same deal except you get £80 cashback after your first bill instead of the £160 in stages so whole contract costs you £80 more so about £420 or £23.33 pm which I think is still good for this deal.