This wordpress plugin Allow you to add a rss feed based webslice to your blog...and coming soon permit you add more options to your webslice...(for the moment widget feature!!!)

The webslicer plugin will let you easily add a webslice rss feed item based that users can use as a bookmark for your site, and checks updates out of your site with the new IE8 feature

more info about webslices here: http://video.msn.com/video.aspx/?mkt=en-us&vid=1c321dbe-98ed-444e-9062-942b69edee7e

download latest version from here: http://wordpress.org/extend/plugins/webslicer/