What do I get my boyfriend for his birthday?

My boyfriend's birthday is coming up on June 23. I want to get him something awesome, as for my birthday he got me an amazing painting done by Ocean Clark of Jimmy Hendrix and I know he put an immense amount of thought into it and I want to get him something that shows I did the same. He's a very talented artist and into heavy metal music (his favorites being: August Burns Red, As I Lay Dying, The Devil Wears Prada, and Parkway Drive). He plays guitar in a band as well. I want to get him something unique and special but am finding it quite hard since I'm on a bit of a budget. Any suggestions would be extremely helpful. Thanks!