Unreal Tournament 3 (82% Average on Metacritic) is currently being sold for £12.99 which is fairly cheap.
With the Student Discount of 10% it comes to £11.79
This is achieved by:
1. Use code STUDENT10% and use Google Checkout
2. Use code STUDENT10% and Enter your NUS Card number and pay as normal
Note: The first option does not require an NUS Card number and works regardless as to your Student Status or not - but you may feel guilty for a couple of minutes! ;-)