I was a big fan of the Hitchhikers Guide to the Galaxy when it first came out (I listened to the radio series, bought the records, watched the TV series, and still own a real Marks & Spencer Hitchhikers towel which has part of the script about Knowing Where Your Towel). The latest BBC Radio 4 series, which picks up from where the first two radio series ended, has now finished, so I thought I might mention that that Douglas Adams also wrote a text-based adventure game, loosely based on the book, in the early 80s. No graphics, just text and some very lateral thinking problems to solve. There is a short clip of him talking about and demoing the game on TV (“Micro Live”, an early BBC program, if memory serves me) on a Commodore 64 and talking about how fiendish the game - http://www.bbc.co.uk/radio4/hitchhikers/gamehistory.shtml.
The good news is, an on-line “20th Anniversary Edition” version of the game is now available, with an improved user interface, and some quite nice graphics. Even better news, there are plans to build a new version.
The original Hitchhikers Guide to the Galaxy game was created by Infocom, who produced a number of adventure games, and in their day, lead the field in “interactive fiction”, though there were a few
So, have a go at playing these great interactive fiction games. If you want to play any of the Infocom games mentioned above, you will need an interpreter program to run them, and there are versions available for various machines, such as the PC and Pocket PC (http://www.concentric.net/~Twist/WinFrotz/) (if anyone knows of a Tablet PC version with proper ink support, please let me know!). If you get stuck, there is help out in the form of on-line InvisiClues (the original clues used invisible ink that required a special pen to reveal the answers).