College kids are known for not having money to burn. They never have to go hungry with a microwave in their dorm room to heat up their instant noodles or their day-old pizza. A 700-watt or similar small microwave is ideal for the college student to make his college experience a little more enjoyable. You could also send a care package full of microwavable meals along with the microwave.
A magazine subscription is fairly inexpensive and a gift that has legs. Instead of enjoying it just once, the college student gets to enjoy it every month for a year or more. Pick a magazine that you have seen him reading in the past or that covers a subject that he has interest in. If he is studying to be an archaeologist, National Geographic or a similar magazine may be a good choice. If he is into racing, then "American Motorcyclist" might be a better choice.
Although the number of women who are serious gamers is increasing, video gamers are still largely young men. For students, the games are a method to unwind. You can give video games by sending a gift certificate for a store like GameStop or buying actual games that you think he might like.
After all the hard work the student puts in during the semester, he needs some time to unwind. Send him to see his favorite professional sports team in action. He will get a chance to yell and boo and have a great time while cheering on his favorite team. Letting it all out will be the stress reducer that he needs to go back to class the following Monday full of vigor.