I got a Playstation 3 40GB console with 2 free games from Argos today by doing the following...
Go onto the Argos web site and add a PS3 60GB console and 2 of the special offer free games for it to your basket. The PS3 60GB should come up as being out of stock because it's discontinued and now in short supply. Leave all the stuff in your basket and go back and add a 40GB PS3 console and go back to your basket again. The 2 games should still show as being free.
Choose to reserve and collect it all at a store with stock and print off and take the confirmation e-mail that Argos send you and it should be game on!
Expect them to have to jiggle things about a bit on the till to get the offer through and try and avoid whistling and looking up at the ceiling.
Lucky me had £65 worth of Nectar points off it too which brought it all down to £234.99. Pretty pleased.