image from here.
Boys are always, always the hardest people to buy for. Boyfriends, dads, brothers, cousins, friends who are boys - always hard.
But then again...I'm pretty sure they think girls are hard too.
There are a few things that are generally always a good bet. For instance - my little brother's clothing got washed in the washing machine yesterday with a pen in a pants pocket, so he might need some of these or a pair of these to be hiding under the tree this year. Plus - there are things that guys are never going to buy themselves but still make great gifts, like this with one of these (engraved), these or (if you've received a hefty Christmas bonus) this.
Boys (men...?) also like to build things. Build things...and take things apart. Gift cards to Home Depot or Lowe's are always a good bet, and if you're really ambitious you could try to pick something out yourself. One very useful thing to have around the house (and I know this because I've stolen my dad's once or twice since moving in to the apartment) is a good quality drill, but that all depends on your gift-receiver's level of expertise. Maybe he just needs a good hammer and a measuring tape...
Any guy you're buying for, with the exception of a 12-year-old who is into electric airplanes, will appreciate one of these. They come in all shapes and sizes from tiny little Weber charcoal grills, to big "outdoor kitchen" type grills so finding one in your price range isn't too difficult. Plus...you might get a nice steak dinner out of the deal. Good ideas for the guy who just moved out of his parents house for the first time ever? How about one of these. Or a nice set of these. Or even gift certificates to great take-out restaurants.
And sometimes it's just thinking creatively that works the best. What about a "gift certificate" for one shopping spree in the grocery store. Or all the fixings for his favorite meal. Dad's usually appreciate things that focus on their kids (even if you're 22) so picture frames with family photos are good ideas.
If I had all the money in the world I would have bought my Dad a trip to the bowl game in Phoenix this year, because he likes the Horned Frogs almost as much as I do...too bad he's having to help me pay the way for myself.