2,100 MS Points - £14.89 delivered
Civilization Revolution, Xbox 360 - £8.89 delivered
Overlord: Raising Hell, PS3 - £11.89 delivered
PaRappa The Rapper, PSP - £5.98 delivered
New International Track & Field, DS - £10.80 delivered
It appears that CD-Action are giving away free downloads of Speedball 2: Tournament. They are giving out serial numbers which you then put into Steam.
Head here, and enter your email address. Or if you prefer to not get any spam, use a disposable email address.
Once you have entered your email, they will send you a serial number for the game, which you enter into Steam in the "My games" tab, under "Activate a product on Steam".
I can confirm that this works, my copy is downloading right now. The game normally costs £13.99/€19.99/$19.99.
Update: Party is over now, looks like they have taken it down. I have a few spares, which I will release in different creative ways throughout the day.