What toys to buy for my cat?

My cat's favourite toy was the plain old tring on a stick. You can get these little toy mice that are attached to a string which you can dangle around and get your cat to chase. my last cat was very playful, she'd play with bits of paper and even the lids from juice bottles, but my cat before that didn't play at all. All cats are different, maybe Milly just isn't interested in toys :)