Darth IB said:
As for games, I'm not too sure though. Or actually, they could make Farmville almost interesting.
DUUUUUUUUUUDEEEE-wait...that depends on how you mean it. The first thought was farmvillagers being happy, pulling up their beetroot or whatever when suddenly Nessie writhes across the screen toward a duckpond, taking all their animals, crops, land and misc. items with it. which was funny in the "ha! my sister would be so angry if that happened to her way"
then i thought "oh gosh, maybe this guy is seriously considering the fact that it would be fun to save up to buy a chupacdbra, which he could milk once a day or something". then a final thought was them being able to buy 'the pond jumper' and train it to go and...'help out' at their friends farms *puts on sunglasses/takes them off*
ahem, aside from the non-funnyness, i don't really know of any traditional British mythological creatures...aside from the ones explored in video-games already (or at least in Lord of the Rings).
J.K. Rowling had some good ones though, in that "mythical creatures and where to find them" book she did for charity. such as the massive Scottish hairy arachnid-like Mammals that were once people, but got turned into these monsters by wizards and in revenge killed the wizards, but then realised afterwards that meant they had no way of returning back to humans... probably doesn't count though
Slenderman? he's a german mythological creature and he scares the crap out of me...he'd be brilliant in a game...or rather, always being glimpsed further away in the background of the game, occasionally being seemingly closer. and never ending up being a semi-chubby boy with his face painted white

I'M LOOKING AT YOU MARBLEHORNETS