A Blink of the Screen collects short fiction from the entire span of Pratchett's career, from 1963 (he was 13) to 2010. 
 This is a delightful collection that includes such gems as an ad man who gets the Devil to repent by making Hell a living hell; several scathing pieces of political and social satire; a time-traveling "Merlin" who accidentally makes a girl the heir to Camelot; what happens when Granny Weatherwax is nice to people; and the Ankh-Morpork national anthem. Bonus: don't argue philosophy with Death. 
 Pratchett's sense of humor shines forth in all these pieces, and they create a nifty timeline of his writing style and how it developed over the years. 
 Not all the pieces will appeal to everyone (I glazed over at a sports-related one), but if you like Pratchett, most of these stories are delightful.