I'm using Page Viewer WebPart to display my applications in WSS
website. All my applications are running under same server, where WSS
site runs but under different website. My applications are NOT Single
Sign-On enabled. Here I'm trying build one. So my question here is, is
there any way to get user details from wss website (ie., the same user
name from right hand corner of a WSS screen). I know it is windows
authenticated when user login for the first time, but when we sign in
as a different user, I'm not sure how to get the user detaills.

I know for sure, someone might have come across same situation.