Here's an example of creating a feed of your Flickr contacts' favorite photos using RSSBus, which makes complex feed parsing/manipulation tasks easy. In my next post after this one I'll talk about how you can use RSSBus caching so that you can control which items are returned in the actual feed (for those with large numbers of contacts or favorited photos). For example, if this feed results in 400 photos for you, successive requests for the feed will not continue to return 400 photos - but only the...