1] coat of arms
one thing i've noticed in glitch is a lack of group or user icons. avatars should work fine for users, but groups might also need visual identifiers. for example, to visually mark a group owned teleporter, house etc. or to appear on group uniforms, pins, sashes.
the current system for generating personal avatars is really slick .. maybe a similar system for creating a group 'coat of arms' from a variety of components?
2] group houses
i'm pretty sure these are already in the works, but a place to communally hoard items and currants would be really cool. maybe by using a piggy bank!
3] work parties
taking the "following" to the next level. following someone could grant the leader the ability to use any skill that a follower possesses. also, perhaps, the ability to use an item from a follower's pack [upon approval].
this might provide incentive to band together into work parties, and give followers some time to relax and socialize while still accruing XP and 'getting things done'. it might also be much, much less tedious than achieving the same end by constantly trading items back and forth.
4] assembly pendants
a group member could call an "assembly" by going to a group owned teleporter and activating it. all group members wearing a "group pendant" would be presented with the option of teleporting to the assembly point.