what are you waiting for? download the zeal 1.1 source or linux executable, which provides terminal and x windows versions of zeal. zeal's source is available under the terms of the gpl.
zeal 1.1 contains the following improvements:
zeal uses a random number generator that was released under the lgpl. zeal's version contains some trivial modifications (basically, i removed main and renamed the file); for the original version, please see the mersenne twister home page.
still reading, eh? well, if you want to know more about zeal, here's the introduction from the readme file:
zeal is a z-code interpreter capable of running version 1-5 and 7-8 story files. if you don't know what this means, have a look at graham nelson's inform page for more info about interactive fiction, the z-machine, and inform. also, the if-archive at gmd.de has tons of software and information related to interactive fiction.
zeal is written from scratch in c++ and uses the glk interactive fiction i/o api and a pseudo-random number generator called mersenne twister (see acknowledgments below). it relies on very few machine or system dependent features, and those that it does rely on it attempts to abstract away. some parts of the z-machine specification are as yet unimplemented, but those parts are infrequently used by games; in fact, every game i've tried to play with zeal works just fine or doesn't work for a "good" (i.e. known) reason.
if i was selling zeal, i'd put these bullets on the box:
to be perfectly honest, though, zeal's feature set is basically a subset of the features offered by some of the other interpreters available (most notably nitfol). why bother, then? zeal actually started as a random coding challenge and ultimately became a usable program, so i figured i'd give it away to anybody who happens to be interested.