If you were to log in, you'd be able to get more information on your fellow community member.
It's Texis, at Thunderstone, and their webpage for that is here.
Since the time I found and wrote about them, I've come across www.atomz.com which indexes only up to 500 pages but which has an advanced option that's easier for users and which also indexes results of cgi runs.
It doesn't do boolean searches but sort of emulates them in a limited way which is easy-to-use. Results are much more detailed, showing you context for each page.
Also it lets you re-index your site at anytime while Thunderstone Texis...