I love knitting but all the yarns I crave are mightily expensive. So generally I buy cheap cute colours and pretend they're just as good. But recently, a very special Aunty (Mandy, if you read this, thanks!) of mine made a suggestion that I thought was blimmin' brilliant.
The idea is to scour the charity shops (like you would for old clothes still bursting with awesomeness) and look for good quality knitwear. Most knitwear is made in pieces and then sewn together so you only need unpick it and it should unravel beautifully. I did this with a big jumper recently that cost me $15 and now I've got three big balls of luxurious glossy cream yarn.
One thing I would advise (although I haven't tried) is that I don't think this would work on mohair or the like, I know I've always struggled to undo anything I've knitted out of that sort of yarn, all the fluffy hairs get all tangled.
I was also recommended that this is a good way to get your hands on some quality buttons.