I need to find the perfect gift. Help?

So, it's sort of a long story. I'll try to keep it short and sweet. The boy I'm in love with has an ex girlfriend who still likes him. And, well, he tends to fall for her all over again. His birthday is coming up and I want to get him an amazing present, better than anything else. But, I'm below fifteen, and can only spend up to $25. I can probably fudge it a little. He loves football (Broncos) and the guitar. Though any suggestions help.