It seems that Firefox can use ProfileManager by
but then it seems like if a profile "work" and another profile "personal" are created, you can't have them side by side running at the same time? (either in 2 windows or 2 tabs).
firefox.exe -p work firefox.exe -p personal
the second time, the firefox is using the "work" profile again.
Any way to make it work? IE 8 can have a "File -> New Session" but you have to log in every time. You can't make them as profiles and remember the sessions it had with gmail, etc. (need to do a login again)