Play Video Games
Fragging each other in a deathmatch or swapping paint in a high-speed auto race may not seem like the best (or safest) way to bond with your boy, but as long as the two of you are stationed in front of the TV, murderous rampages and suicidal driving techniques can make for excellent father-son time.
Of course, you don't have to blow up each other or get behind the virtual wheel if you don't want to. You can play through an entire football season in the heat of the summer or practice your pixilated fighting skills if you'd like. If your son is too young for football games or martial arts (or you guys just want to play something a bit more relaxing), the two of you could hop into a pair of virtual overalls and save a kidnapped princess, or sling agitated birds at fortified pigs on your cell phone.
It doesn't matter what you play or how you play it, just spending time with your son in a comfortable and fun environment is going to bring you closer together.