I know a few off the top of my head, here goes

animImportExport.bundle - Exports and imports animations

cgfxShader.bundle - A custom hardware shader creater

nearestPointOnMesh - Finds the nearest point on a mesh from a specified point (a maya node that, I think, replaces closestPointOnMesh)

ikSpringSolver.bundle - Creates a IK solver that goes accross multiple joints

studioeImport.bundle - An importer for Alias Studio

vrml2Export.bundle - Exports to VRML (interactive 3d type programme)

A lot of the other s look like little tools and various exporters/importers