I have been experimenting with some search engine widgets in my test blog.
Widget: Blogbar
URL: http://www.blogbar.org/
Description: Blogbar is a free search engine bar you can add to your blog. I found this at Google Gadgets.
Review: This is the nicest looking of the several I tried. It doesn't slow down the loading of the sidebar or present any other problems. Unfortunately it has too many search options I don't use so it's not for me.
Widget: BeeWak
URL: http://www.beewak.com/
Description: Another search engine widget I found at Google Gadgets.
Review: The BeeWak widget isn't as nice looking as Blogbar's but it works fine. If I used Beewak I would probably use a text link to the website to save sidebar space.
Widget: Technorati Searchlet
URL: http://www.technorati.com/developers/help/searchlet.html
Description: Technorati Searchlet "enables site-specific and weblog search across Technorati's entire database of posts." It is currently in beta.
Review: This is an interesting idea and I would like to see how it develops. I am most interested in the search this blog feature but I haven't been able to get it to work yet. It may work if embedded into a template.
I am not sure if I would use the searchlet in my blogs because Blogger already has several search features built into it.