This plugin allows users to be automatically awarded a badge based on a configurable number of user points (requires the User Points plugin). Additionally, badges can be manually assigned by an administrator and locked so that the badge will not change as points are gained or lost.

The badges are displayed on the lower right hand corner of the users icon (see screenshots). This is done by overriding the default profile/icon view and adding a css overlay on the fly. For the best results you should use 16x16 icons. IconArchive has a good collection of 16x16 icons.