I've posted this elsewhere but thought it warranted listing on its own.
If you reserve two games for store pick up then one of the games is priced at £10.01, but if you make sure the other game is out of stock then go through and reserve, it reserves the game that is in stock at £10.01. I've just done that and have reserved Heatseeker and Splinter Cell at £10.01 each!!
You might have to play about with it a bit but it does work. I'll know for sure tomorrow when I pick them up but the self serve should still give them at the price quoted with your reservation number.
Can't seem to get the link to work properly, sorry I'm a newbie here!!