Obie walks through the technique for getting more search engine-friendly URLs and still retain the ease of use with auto-incrementing ids.

It’s the same technique we used on the new 37signals blog engine to get urls like http://www.37signals.com/svn/posts/247-calling-all-basecamp-customers-in-nyc-or-chicago.

The 247 is what Rails see and calling-all-basecamp-customers-in-nyc-or-chicago is what Google will focus on. Have your cake and eat it too!