How do I remove a badge from my profile?
Foursquare was originally designed as a way for people to check in and let their friends know where they were partying for the night. Over time the service has grown to encompass much more than that, with people checking in at every location they visit. Several of the badges from those early days still exist, however, and what was at the time seen as a funny joke is occasionally found to be offensive by some users.
To remove a badge from your profile, simply visit your history page and remove the checkin that earned the badge by clicking the small “x” to the left of the checkin. For instance, to remove the “I’m on a boat” badge, simply delete the boat checkin. This will remove it from your profile, but you could still earn the badge again in the future.
Update (5/4/12): The method for deleting a check-in has changed slightly. See this FAQ for more information.

Ha! Self-conscious about a #Foursquare badge? Here's how to remove it from your profile! http://j.mp/bTaZCa
[...] This post was mentioned on Twitter by Eric Andersen, Joel Hughes. Joel Hughes said: RT @eric_andersen: Ha! Self-conscious about a #Foursquare badge? Here's how to remove it from your profile! http://j.mp/bTaZCa [...]
[...] venue where it was earned. If a badge gives away more information than you’d like, you can remove the badge from your profile by deleting the checkin where it was earned from your [...]