Over the weekend I released clevercactus feedexplorer, a simple free app to browse the data from the Share Your OPML commons (thanks Dave for making this resource available!) and choose feeds that you find interesting, then allowing you to save them into OPML files that can be imported into a news aggregator. It runs on Windows, Mac OS X, and other OSes.

Here is the page with installation instructions and a short user guide.

If you can, take a moment to read the user guide as it explains how to change the sorting, perform searches, etc (Btw, I think the UI is pretty self-explanatory, but reading the doc should leave little doubt as to how to do something :)).

Note: if you have any problems with the installation, please take a moment to read the installation page, as it answers common questions and problems.

Another Note: the first time the app loads it will obtain the data from the site, but afterwards it only downloads the changes (through combined use of Etags and Last-Modified HTTP headers with the data in the main feed, which also includes change dates). Additionally, transfers use GZIP compression to minimize both server load and download times.

Yet Another Note: I find the incremental search function to be strangely mesmerizing. :)

Screenshots
Here are a couple of screenshots (click on the images to see a larger version).
feedexplorer running on WinXP:

And under Mac OS X (thanks to Erik for the image):

A bit of background
As I noted a few days ago, Dave had released Share Your OPML. After that he released an SDK to allow others to tap into the data and provide new applications. I had an idea last week for an app that would use the data, but was too busy to do it. Finally, on Saturday morning I decided to let off some steam by coding something else, and this application seemed like a good idea: it had a simple goal, and I could do it quickly. In the end it took me about three hours to write the app, and a couple of hours more to finish the docs and the install pages. :)

So what's the idea?
The idea is that you can peruse subscription lists in two ways, one by looking at them starting from the feed and being able to see who subscribes to it, and two by looking at people that have shared their sub lists and see what they subscribe to individually. As you look through the list you can choose feeds you find interesting and add them to your own subscription list, which you can then save into an OPML file in your local hard drive to import into your news aggregator.

Now, there are other ways of getting subscription lists, but what I found interesting about this dataset is that it tells you who's reading what, which maybe leads you to find feeds (that you'd otherwise not look at) simply because someone you know is reading them--sort of an implicit recommendation system. If your own feed is listed, you can find out some of the people who are subscribing to you.

And what's feedexplorer have to do with clevercactus pro?
Well, eventually functionality like this would be added to cc pro. I think that it would make it easier for people to subscribe to feeds within the app, find out what's going on in the blogsphere, etc. feedexplorer, however, stands on its own as a simple, free utility that is generic and not tied to any particular product.

So that's it! And, as usual, comments welcome (if I have to close the comment section of this entry due to spam, you can always send me an email).