FeedBlendr - lets you combine a bunch of feeds into one

FeedBlendr will grab all the feeds you enter and blend them up into a nice, thick, 'river of news' smoothie. You'll get a URL where you can subscribe to everything all at once.

FeedBlendr takes the feeds you give it, pulls the individual entries from each of them, attempts to sort them in date order (combined across all feeds) and then provides you with a new, blended feed of all entries.