I’ve been meaning to install this for a couple of weeks now and just got around to it tonight. At the bottom right there is now a “Search this site” link, once clicked you are presented with a search box and pulldown. “My site” searches this blog with Google, “The web” searches the whole web with Google and the “Blogs I read” option uses Micah Alpern’s great tool linked above to search all the sites who’s RSS feed is listed in the OPML file I export from NetNewsWire, that way I (or you) can narrow a Google search to only sites I use / read every day, in Micah’s words;
If Googling my weblog is like searching by backup brain, then searching all sites in my RSS news aggregator is like searching the brains of people I respect and find interesting.