Basically, one of the best adventure games of all time, along with
Monkey Island. It has a lot more
plot than many of the modern 3D games and is
incredibly funny. It was the only SCUMM adventure besides Maniac Mansion that was still released for the
C64.
That's why some guys started the "Zak McKracken 2" project at
http://zak2.adventuregamer.com/
and the novelised version of Zak McKracken at
http://www.fortunecity.com/meltingpot/neches/158/zak.htm
The game had an excellent soundtrack, of which two remixes were released by The Dead Guys. You can find them at
http://www.audiofind.com/the_dead_guys.html