Mostly Harmless is the best of the three Hitchhikers guide books I have read. But I have just finished 'The Sacred Art of Stealing'
by Christopher Brookmyre. 5/5! (This isn't an impulsive score, I really do wish all books were like it.) Best described as Glaswegian satire, the first half is about an elaborate heist and the second half would be spoilt if I were to tell you about it.
Also, Carl Hiaasen is a Floridian version of Christopher Brookmyre, he's very good too. Characters range from a semi-crazed ex-governer turned wandering hermit to a violent and armed elderly woman who is fanatical about environmental causes. Not to mention a sexually deviant dolphin.