a good search script?

[sickkittens]

Can any one recommend a good search script to use internally on a site?

[HEAT]

http://gossamer-threads.com/scripts/links-sql/index.htm

[sickkittens]

http://gossamer-threads.com/scripts/links-sql/index.htm

I'm cheap. I'm looking for something free that can just do a simple search. I've found a couple (that have ads) but seeing if there are any other simple ones w/o ads.