Ansel, which is the Horde Project's photo application now has support for RSS feeds. 

Both RSS 0.91 and RSS 2.0 are supported, and the later includes support for the media namespace extensions. What this means is that people can now subscribe to your public images, and if using a feed reader/aggregator like Yahoo, view thumbnails of your images from the feed itself...just like Flickr's RSS feeds. 

There are a number of 'photo streams' available via RSS.  You can subscribe to streams from a particular user, a specific gallery, a stream for all publicly available images, or even a stream for all images tagged with a specific tag.  Also planned are streams for particular categories. To subscribe to a feed, use a URL such as the following in your feed reader:

Entire Ansel site	http://path/to/horde/ansel/rss.php
Specific user	http://path/to/horde/ansel/rss.php?stream_type=user&id=username
Specific gallery	http://path/to/horde/ansel/rss.php?stream_type=gallery&id=gallery_id
Specific Tag	http://path/to/horde/ansel/rss.php?stream_type=tag&id=tagexample
­If you would prefer a RSS 0.91 feed (without media extensions) add type=rss to the parameters.

Ansel is not yet released in a stable version, but is quickly nearing a 1.0-alpha release.  It is currently available via CVS snapshots or directly from the CVS tree.

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