Popped into my local WH Smith (Westfield Centre, Derby) and picked up LittleBigPlanet on the PS3 for £12.50. Not quite the cheapest it's been in the past but currently I can't find it for less. Great game for not much money!
Worth noting that the majority of the console games in the store were also reduced, looks like they are having a clearout. Not a huge amount of choice at the Derby store, but perhaps more choice at others? I also picked up Fallout 3 (PS3) for £12.50 but it's not the GOTY edition so probably not as good value as LBP.
"Play With Everything!.
Welcome to LittleBigPlanet, an amazing new world where anything is possible. Take control of your very own
Sackboy in the search for clever creations and cool stuff. Then build your own unique content and share the fun
Join Sackboy and uncover the secrets of LittleBigPlanet.
Use simple tools to make whatever you can think up.
Go online and share everything with the LittleBigPlanet community."