Blurring

A friend of mine is trying to make a map and wants to know if theres a way to go from normal view to a blurry screen. And if its possible can someone tell me how it can be done? Also can the reverse be done?

Well I suppose you could add fade filters, with a scratchy looking alpha layer, and then use the shake camera action (very faintly, nothing headache inducing) to screw up the player's vision. Can I ask what it's for? To make the player feel drunk? or as if they've just been punched in the head?

Balth's idea is pretty good. It's probably also the only practical way to do it.

Blurring effects take a fair amount of processing power. Enough that even if the game engine had that function built into it, it would be almost useless because it would kill your computer everytime you tried to apply it.