Presents for Friends
You have a lot of opportunities when picking up presents for your friends and you have actually no restrictions as for those. No one can forbid you to buy anything you like and anything your friend will like. Friends are people who know us better than all other people and we also know them better than all other people. So, we need no advice in this case.
Though, some pieces of advice may still be given. People are different and they are of different characters and so may get offended with the things you recognize as funny things. See, the sense of humor is such a peculiar feature of people that may be of great help for them and at the same time of great harm for them, remember about it.
In case you like jokes and you want to make you present the best joke for you friend try to do your best in order not to hurt peoples' feelings with a gift. They may be people of different sense of humor and so they may recognize your present as the offensive one, and it will hurt them no matter on the kind relationships you have, you may spoil everything.
Be careful when kidding because your friends may be a people of different sense of humor or you may appear to be a person of particular sense of humor that is common for you only. Care about feelings of your friends.