My brother's birthday is coming up and I'm stuck. What do you get a 15 year old boy?

I asked him what he wanted and he said a 'SnapBack' which turned out to be a hat, so I ordered him that along with a hoodie he wanted. However, I remember how boring birthdays were when you just got clothes, and you knew what you were getting. Does anyone else have any ideas for something else I could get him? Nothing too expensive and I can only order online as I'm not in the UK atm. Just an idea about my brother, he has everyyyything already and he likes to think he's 'cool'.