What should I get my boyfriend for his 23rd birthday?!?

We've been together for so long, we've pretty much bought each other everything there is to buy. So last year I made him a chess board and he loved it. I told him not to even get me anything for my last birthday because we don't want to buy something, just to buy it, you know? He asked to read this collection of books I have that I needed for a cl last semester so I wrapped some ribbon around the stack of books and I'm going to give that to him, but he's already seen those books and knows I have them. He doesn't know I'm giving them to him though. I wanted to do something special for him this year and I just can't think. It might seem like I'm a bad girlfriend for posting this question online, but we love each other more than anything. I'm just looking for some brainstorming ideas...