I came across a second site that's hosting the Infocom games: PortableQuest.com. They only have the 4 Zork games (Kindle Quest had 12 games), and it appears to have the same basic set of commands as KQ.
Many people cut their teeth on the imagination fueled text adventures games released by Infocom back in the eighties. Whispernet combined with the handy keyboard and the limiting browser made the Kindle perfect for a text-based adventures. We programmed an interface specifically for the Kindle that lets you play a handful of the Zork-like adventures that we spent many of hours of our youth. Save game is supported so you can come back at a later time without restarting. Let us know what you think and how we can improve it!