That had to be embarrassing...
Some More of God's Greatest Mistakes is a book briefly mentioned in The Hitchhiker's Guide to the Galaxy, part of a trilogy -- an extended trilogy, in fact, much like The Hitchhiker's Guide itself.
"The Hitchhiker's Guide to the Galaxy is a wholly remarkable book. Perhaps the most remarkable, certainly the most successful book ever to come out of the great publishing corporations of Ursa Minor. More popular than the Celestial Home Care Omnibus, better selling than Fifty-Three More Things to do in Zero Gravity, and more controversial than Oolon Colluphid's trilogy of philosophical blockbusters Where God Went Wrong,Some More of God's Greatest Mistakes and Who is this God Person Anyway? It's already supplanted the Encyclopedia Galactica as the standard repository of all knowledge and wisdom, for two important reasons. First, it's slightly cheaper; and secondly it has the words DON'T PANIC printed in large friendly letters on its cover."
There was also Oolon Colluphid's fourth book, Well That About Wraps It Up For God. Unfortunately the only scrap of text that exists on Earth is from Well That About Wraps It Up For God, and isn't actually very good (I will forgo posting it here, as I suspect that I am already all too near to violating the E2 copyright policy). Douglas Adams wrote reams of nonsense, but apparently the God books hit a nerve; while Google finds only 1530 results for Celestial Home Care Omnibus and an amazingly low 389 results for Fifty-Three More Things..., there are over 4,000 results for Some More of God's Greatest Mistakes, and nearly 6,000 for Where God Went Wrong. Apparently the Human race agrees that something has gone wrong in the God department.
"There are no mistakes, no coincidences. All events are blessings given to us to learn from. Especially platypuses."
-- Elisabeth Kübler-Ross