Pertaining to the default authetication problem (login prompt) that people experience when opening web pages, i would like to suggest this be a feature added to the RC:
Click on this link and it shows you how to use the protocol for username:password in the URL. Although IE prohibits this usage, the above link explains how to modify 3 simple registry settings to allow this. A user could simply do this themselves to have a permanent setting on their machine, and thus be able to utilize the username:password URL syntax.
However, the selenium server already modifies registry settings to specify it's own proxy - shouldn't it just as easily be able to modify/restore this setting for running in IE? I think that it would be an imperative feature to add to the RC for the next release.
The only thing the user should be responsible for is to add a <username>:<password>@ into the URL of their selenium.open() command. (Or perhaps there could be a setUser/setPassword command called before the open statement?)