Each BuddyPress user can select as many external RSS feeds as they want. They will be aggregated into their activity feed automatically, with a title, an excerpt and a link to the original post.
Select any kind of RSS feeds that will be agregated in your activity stream.
Uses WP-cron to update feeds automatically.
Download and info: http://wordpress.org/extend/plugins/yd-buddypress-feed-syndication/