I've noticed all the cracking £19.99 deals for this game are expiring due to no stock so I went for a look.
Resistance: Fall of Man game for Sony PlayStation 3 for £17.61 at Microdirect! Just add your delivery charge, mine was £2.99, it might be cheaper in the rest of the UK as I live in the sticks.
So £21.13 is still a decent price.
Want it before Christmas? Add express delivery - approx £5.99, makes it £24.65 - if you're desperate for it.
Is there any google check out offers? ie 5 quid off?
This is definitely ne of the best games for the PS3, I have it now about 8(?) months and still play it!