The Embarassingly Sexual Gift
These gifts aim for crude suggestiveness. Examples include sex toys, pornography, T-shirts about sex or nudity, and objects designed to resemble sex organs (such as penis-shaped lollipops and breast-shaped computer mice). They are best among peers who share a bawdy sense of humor. Similarly, while they are appropriate at a bachelor party or divorce shower, they would be less welcome at a family birthday dinner.
The "In" Joke
Any object that calls to mind an embarrassing or funny adventure from the life of the recipient will not only amuse him, but also provide an opportunity to tell the story. The gift can be an object that featured heavily during the event, or the one thing that would have made the incident run smoothly. Other choices might be clothing from a shared school or organization or a bottle of cheap liquor that the group used to enjoy when they could afford no better. Before choosing this sort of gift, be certain newcomers to the group do not feel left out.
The Gross-Out
Joke shops are full of fake vomit, dog doo, bugs, worms and other things designed to disgust the poor unfortunate who first opens the box. Best for casual events, this is still a staple gag gift. Another example is a T-shirt with a slogan so offensive the recipient can never wear it. Much like the embarrassingly sexual gift, this kind of present depends on the recipient and the audience.
The Ironic Gift
This gift is more subtle than the others: an object that is painfully and obviously useless to the recipient in every way. Examples include a funny T-shirt for a nudist or a "Dummies" book for somebody who just got her Ph.D. in the subject of the book. Chosen well, this kind of gift can help your friend celebrate an accomplishment or close the door on a chapter of his life.