BrammoFan (a.k.a. Harry) with his eagle-eyed vision for all-things-brammo noticed a motorcycle dealership in San Francisco that's now renting Enertia's by the half- or full-day.
See:
http://brammofan.wordpress.com/2011/08/30/rent-a-brammo-arrives-in-san-francisco/
http://www.dubbelju.com/_blog/Dubbelju_Blog/post/Dubbelju_goes_electric!/
http://www.dubbelju.com/_webapp_3976709/Enertia
Rates: $69 for 1/2 day, $99 for full day
They can rent you a helmet, jacket, etc. The rental includes things like 24 hr emergency service.