A few interesting XYZZY related sites:
Want to play Adventure on your own PC? We've located an MS-DOS version that
runs from the
Windows command prompt. A .zip archive of the game and some
related documentation is available.
Even the folks at Sun remember Adventure. There is an easter egg hidden
in the
administrative interface of the iPlanet 6.0 server that plays
the game.
On a related note, information on some of the old
Infocom adventure type games can be found
here.