Do you like Kellogg's cereals?
If you do then make sure you pick up the promotional boxes where you can get a unique code. Once you have 3 unique codes, enter your codes at the Kellogg's website and pay £1 to cover the P&P.
Then all you have to do is wait for the postman to bring you your new towel(s). Find out more about this free stuff at the Kellogg's website.