Searchpath
Searchpath, developed by Manton Reece, is a neat little search box you can easily embed on your website or blog. All you have to do is add a little Javascript snippet to your site (in the footer or wherever else you might want a search bar) and Searchpath will index everything so that it can be searched by visitors later.
The results pop up right next to the search field, with the relevant keywords highlighted. It works quite well on iOS browsers, which I very much appreciate. Searchpath even pulls CSS styles from your site so the results fit right in with the rest of your text (although you can edit these CSS properties if you wish). You can also edit the placeholder text.
There’s a free demo of Searchpath that limits search results to two hits, but you can pay $8/month for a full account with all the bells and whistles.