I like this - its like a portable google search for your browsing

History SearchFlock comes with the open source Clucene search engine built in. Each time you visit a web page, it indexes all the content on that page so you can easily retrace your steps later. Pages you've starred as Favorites float to the top when you do a History Search. History Search is stored locally for privacy. For more privacy, you can wipe it out using the Clear Private Data command.Example: 1. Visit some interesting web pages, such as Yahoo News. 2. Start typing a few letters of a search query (for example "tech") into the search box. 3. After you type a few queries, a menu appears showing you matching results from your browser history and pages you have starred. You can use the keyboard to navigate through the menu. 4. When you press Enter, a normal web query is done using the search engine you have chosen.

Flock