Panasonic has been working on its Hospi hospital delivery robot since back in 2004. When it was first introduced a decade ago, it was too expensive and not capable enough to effectively compete with existing hospital infrastructure, and Panasonic managed to sell a total of two (yes, two) robots.
But it's now 2014, robots are way better, and healthcare is way more expensive than it used to be. After a reintroduction at IREX in 2013, the newest version of the Hospi robots have been successful enough in hospital trials that Panasonic is actually starting to sell them again.
Hospi is essentially an autonomous cargo container. It's designed to ferry small but important things (like drugs) from one place to another, which is a critical task in hospitals, and usually requires a human to make a dedicated trip to a pharmacy that may be on a different floor of the hospital. This sort of thing is a waste of time for highly trained medical professionals, which is why a robot makes sense to have as a delivery system.
One of the big reasons that we're seeing robots like Hospi providing reliable and cost effective solutions in places like hospitals is that robots are getting to the point where they can comfortably deal with semi-structured environments.
A hospital is flat, constrained, well defined, well lit, and you can adapt parts of it (like elevators and doors) to be robot friendly. There are still a lot of variables, like things cluttering up hallways and humans moving around unpredictably (humans do this a lot), but for the current generation of service robots, these variables are now manageable.
Dynamic path planning has come a long way, and sensors are cheap enough that you can build a robot that won't cost a fortune and can avoid running into people or obstacles while trying to get from one place to another. We've seen these capabilities with Adept'sdelivery robots, with iRobot's AVA, and we expect to see it even more in the near future, especially in the form of lower cost platforms.
Five Hospi robots are currently operating at the Matsushita Memorial Hospital, where they've reduced delivery times by over 30 percent. The robots themselves cost US $100,000 each, and getting the hospital set up with the infrastructure necessary to manage them is several hundred thousand dollars more. But once that's all in place it's easy to expand the system, and the maintenance costs are very low.
Here's a video from 2010 showing the second generation Hospi; the robot shows up about halfway through, after the automatic medication dispenser.