I'm a sucker for handmade stuff. Last Vday I made my boyfriend(now my ex) a mix CD with songs that reminded me of us, and I made a cover for it with cardstock, and drew little things that were inside jokes to us, and just things that we were both sentimental about. I made him some toffee, and a journal because we were both into writing.
I would look at pinterest, search DIY valentines gifts, pinterest always gives me good ideas, don't be afraid to do your own thing! Make it special!