Actually, I was just researching this over the last week.
There was one thing I found, but maybe it's not related.
http://soulpass.com/2008/01/24/using...irefox-3-beta/
Basically, it is creating a firefox toolbar with your own links and so forth. But I don't know if it can be used to search your site. Is there a way to make the toolbar and also search other sites?
Then it shows links and a search of your site everytime someone opens their browser, regardless of what site they are on.
(some people may not like this though...)