In the most recent release of RSS Bandit we started down the path of making it look like Outlook 2003 by using Tim Divil's Winforms controls. The primary change we made was change the toolbar. This change wasn't good enough for Thomas Feudenberg who made a couple of other changes to RSS Bandit that make it look more like Outlook 2003. He wrote
Anyway, contrary to SharpReader, you can get the bandit's source code. Because I really like the UI of Outlook 2003 (and FeedDemon), I patched RSS Bandit:
It took about 15 minutes. Mainly I docked the feed item list and the splitter to the left. Additionally, I've created a custom feed item formatter, which bases on Julien Cheyssial's MyBlogroll template. You can download my XSLT file here.
You can find a screenshot on his website. Torsten's already made similar changes to the official RSS Bandit source code after seeing Thomas's feedback.