There is, kind of:
http://kindlequest.com/
Play Zork on your Kindle at Kindlequest
Though they do have the Kindle name on it, it's just a web browser interface, with a minimalist web interface. These pages where ideal for the K2 which has a basic web browser and 3G, so you could play anywhere.
I'm sure if you look hard enough you might be able to find an app or downloadable versions.