There's a lot of shit you could get. If he plays video games, you could always get a used game at GameStop or some shit. Alternatively, if there's anything he really needs (a tool or small tool set, maybe a piece of sports gear, maybe car cleaning products, etc), that could be a good choice. It's kinda hard to say without a price range, but I was thinkin between 30-40 with my suggestions... Personally, I always like gift cards or somethin along those lines, or gas cards, because I don't place much value in material items, and there's not much I need... But some people feel weird about giving/receiving items that have a clear value. Hope that helps haha
Hand make him a card that shows your personality and is about him. Then pair it up with a coupon book that has things like "free shoulder rub this day" "intimate act that day" etc... I've appreciated that more than any other gift. Thank me later.