I just learned from Jack Simpson's genealogy blog at the Newberry Library in Chicago about Genealogy Blog Search. Christopher Dunham of the Genealogue created a custom Google search engine that draws from 150 genealogy blogs that he has identified. I tried several family names before I found one that returned results, but I got good results on state searches in my trial. As Dunham adds more sources to search, the handmade tool will become more useful to genealogists searching for what other genealogists are doing and reporting.
The Google Custom Search Engine looks pretty easy to use if you have an idea. I might make an engine to search book reviewing blogs, or one to search regional bird watching websites. A customized search engine using my favorite gardening websites could be handy. Of course, I could make one with the blogs that I read regularly to make refinding a post I remember easier.
Google has a webpage showing some sample customized search engines. It looks like the possibilities are endless.