I have recently enabled a feature on my Blog which activates Internet Explorer 7's RSS Icon. This line of HTML:

<link rel='alternate' type='application/rss+xml' title='' href=''/>

alerts IE7 to the fact that this site has a RSS feed. I currently have this in my Master Page and therefore it is included on all pages in my Blog. You can put this line of code in multiple times in the of your page for each feed that you publish, remembering to give each a different title and href, either on individual pages or across your site as a whole. Users of IE7 can then use the feature to add my Blog RSS Feed to their IE RSS Feeds Syndicator.