Theranos launched their first location in 2013 (ref here, second article from the bottom). They seem to be unique in providing lab proficiency-testing results. Many other labs however who have been around longer have the same business model. Here are just a few.
Any Lab Test Now has been providing direct access (no doctor order necessary) walk-in lab tests since 1992 according to this page, and has been licensing franchisees since 2007. They publish their prices (click any test for the price) on their site along with testimonials. They have a location finder (on main page) which display hours of operation for each location.
HealthLabs has been providing direct access testing, and publishes their prices (click on a category on the home page to get started), posts testimonials, and has a location finder with hours. They appear to be in business since 2002.
Another direct access provider, True Health Labs has been around for over five years, lists a price and draw location once you have selected your tests, and posts customer reviews.