It's a little dated by now, but this was the original and best spoof of science and modern technology - it was like listening to the whole cast of Monty Python in outer space!
Douglas Adams is brilliant; this is one of the few books I have ever read that made me laugh out loud. I definitely will be reading the rest of the series.
It's a reasonably funny book, but unfortunately the actual decent laughs are few and far between. It's possible the writer was as high as a kite when he wrote it and perhaps one needs to be in a similar state to truly enjoy it. Fry does a pretty good job but he can't make comedy gold out of the material. I'm just surprised it's so popular considering it's mediocrity.