When I first came to second life, I thought those avatars wearing white outfits with text on them were wearing a very popular inworld brand, it took me a while to realise it was actually the fact that the textures hadn't loaded.
There are lots of good ideas in this thread and the other similar post but peole like Qarl and Pathfinder may be able to help with pointing some of the technical hurdles here.
I do like Hamlet's suggestion of a white label viewer, I'd like the ability for sim owners to have their own viewer download for regulars that had information about their sim as the message of the day and the regular textures downloaded locally etc. but that would be a nightmare in terms of management.