Feed(Aggre)gator takes a list of RSS feeds and creates a single list of RSS items from those feeds to be displayed as a widget. You can select how many items you want to display and whether you want to show the entries chronologically or you want to show the latest entries from each feed listed.
You can also opt to display the date associated with the RSS item as well as the author of the item.
Donate
If you like the plugin, consider supporting the author through http://www.brownlowdown.net/webdev/feedaggregator/#donate.