I think that tabbed browsing, which has worked wonders for web browsing (and may work similar wonders in file navigation), can be a feasible, necessary addition to the desktop clients of virtual worlds like Second Life. Rather than the single-tasking that forces a user to view only one persistent virtual world location at a time within the client, tabbed navigation of the virtual world can allow the user, through the user’s avatar, to glide effortlessly between the tabs which contain open locations; the indication of presence can also follow the user between the tabs, allowing other users to know when the user’s avatar is in the tab or not.

This sort of browsing, which can also be applied to virtual earth clients such as Google Earth, can also allow the user to open other locations with a simple middle-click of a teleport link, which will then open in a separate, adjacent tab. This can also be deemed as opening separate instances within the client.

Tabbed browsing of virtual worlds may result in greater capabilities for user multitasking, and can allow for users to WYSIWYGially drag copies of virtual objects from one location in a tab to another location in a separate tab, alot like text links in Firefox.