I got my dad a cool stained-glass style Gamecocks picture frame. He and I both went to USC, so I figure college stuff is doubly appropriate as Father's Day gifts. I hope he likes it.
I gathered pictures of me, my older brother, and my older sister of when we were each like, 1-3 years old, each of them with our dad....then I took em to Kinkos and got a 12 month calendar made. It looked really nice, he was pleasently surprised.