(I don't know what this deal is like for non UK)
Steam seem to have (or have ingeniously designed) a mistake on the pre-order of BioShock 2. Their full price is £39.99 and currently have a pre-order offer of 10% off making it £25.99. Now my maths isn't great but I think that 40 - (10% of 40 = 4) = 36. So take them up on the offer while it is there.
During the pre-order they are giving away BioShock 1 for pc. I already have it so if someone wants it for a few donation credits (which I've run out of but want to give to skwire) than let me know.