Neat little widget for Mac OS X Tiger that is a handy Wi-Fi finder and also a self-updating directory of free and paid hotspot locations, that you might be interested in:

http://www.jiwire.com/macosxtiger.htm

If you don't yet have Tiger, you'll find the previous "directory-only" version of this tool for older non-Tiger systems (OS X 10.3 and later) via a link at the bottom of the page.