This is my favorite Space Quest adventure! The SCI series of 3-D adventures of Sierra On-Line were, in my opinion, the most fun to play. Gorgeous EGA graphics (takes talent to make 16 colors look like VGA, folks!), the intelligent typed interface, a fun and hilarious story, and memorable moments and characters make 'Space Quest III: The Pirates of Pestulon' the best installment in the series. Enjoy sci-fi humor like the "Bowtie Fighter" from the "Cologne Wars" in the garbage freighter, or watching the U.S.S. Enterprise zoom away from Monolith Burger as you arrive.
Don't miss any of the seven games (if you count both versions of 'The Sarien Encounter'!). 'Space Quest V: The Next Mutation' is also a wonderful game. Scott Murphy and Mark Crowe were hilarious, talented guys, whose work is missed.
Anyone with even a passing interest in the series should be sure to check out
http://www.spacequest.net for more information than you'd ever expect to see on an average fansite.