Fellow Pacific NW'er John Chaffee has just released WhenWorks:

WhenWorks eliminates the back-and-forth by allowing others to book time with you online, only when you're free and only during time slots you've defined.

Just share your scheduling link in email or on your website, then sit back and let WhenWorks do the rest!

WhenWorks is an iOS app, and you can check it out and use it for free. Looks like a great idea and app.