Samsung Galaxy S2 for just £200 after Top Cashback. They are currently offering £111.10 for O2 contract. Cost of phone is just £59.99. They have both white and black available. Here's how it works
10.50 * 24 = 252
252 + 59.99 = 311.99
311.99 - 111 = £200.89
no data if you remove it after ordering
It can be even cheaper if O2 gives you 20% discount like some claims if you terminate your contract, after cashback of course.