As I mentioned in my post News Aggregators As Denial of Service Clients (part 2) 

the weblog software I use, dasBlog, does not support HTTP Conditional GET for comments feeds so I'm serving dozens of XML files to each user of Newzcrawler and SauceReader subscribed to my RSS feed every hour.

It also turned out that the newest version of dasBlog also stopped supporting HTTP Conditional GET to category specific feeds when I upgraded from 1.5 to 1.6. This meant I was wasting a huge amount of bandwidth since thousands of RSS Bandit users are subscribed to the feed for my RSS Bandit category.

I decided to download the dasBlog source code and patch my local instance. As I expected it took longer to figure out how to configure ASP.NET and Visual Studio to allow me to compile my own blog software than it did to fix the problem. I guess that's a testament to how well the dasBlog code is written.

Mad props go out to Omar, Clemens and the rest of the dasBlog crew.