In a miraculously short timespan of 3 days, this was made during the summer of 2005.

No specific inspiration, though I found, on a later date, that his (my) voice and attitude bears a remarkable resemblance to Marvin the Manically Depressed Robot from the Hitchiker's Guide to the Galaxy. This was unintentional, but startling, and Douglas Adams has been properly credited. He's a funny guy, really. Read his books.