I don't give presents to co-workers or supervisors; I think it's too likely to lead to bad feelings if gifts aren't equitable or if someone gets preferential treatment based on a more generous gift. I don't know if it's illegal to solicit contributions for supervisor gifts, but at the very least, it seems fundamentally unethical. He'll probably not want to "rock the boat" though; as the saying goes, "The nail that sticks up gets pounded down."