The cinema one is very true though!
It costs under £1 to buy the popping corn, and that'll fill a sizeable bag. We always smuggle it into the cinema - they've never complained so far - and take a bottle of water with you and you'll easily save £5. Given how much tickets cost at the moment it's a pretty good saver - especially if you go regularly and feel that it's not a film without nibbles!
I also do the change thing. Buy one of those smashable pots and dont' put anything under 10p into it. Fill it with all your loose change when you come back from the shops - since otherwise you'll either lose it or waste it. Once it's full, you should have well over £200 - especially if you put the odd note in too! Buy a new pot with the money and start over again. It's really worth doing.
Read up on this site: www.instructables.com , loads of tips on reusing rubbish around the house and how to make things that'll save you cash The obvious one is the duct tape wallet.
http://news.bbc.co.uk/1/hi/magazine/7486417.stm Interesting article on the beeb about this