Microsoft just released the updated version of the MSN Toolbar Suite that includes MSN Desktop Search and now tabbed browsing for Internet Explorer. I was beta testing this on my Tablet and loved it, even though at that time it still had a few bugs. The primary reason I use Firefox or Maxthon is for tabbed browsing and now I can save some space and go back to Internet Explorer. Visit the MSN Toolbar site and download the latest version for yourself.
I still use MSN Desktop Search and love the improvements they made to the final release version. People are still installing it at work and I am spreading the news about this powerful search client.