This plugin provides a sidebar-widget and a template-tag that add an enhanced blogroll to your sidebar. It checks on all your linked sites for which you saved a separate feed-url, when the most recent update has occured.
The age of the most recent post will be displayed under the bookmark.
As the Feed reading blogroll plugin has some limitations (sorting by date being the most obvious), I tried finding a different path. I’ve succeeded with a text widget connected to a Newsgator Headlines script.
What you need is a Newsgator account. Once you have it, add all the feeds you’d like to see in your blog list widget.