'Dear Sir or Madman,'
Yes, I'd written 'Madman' ... in a letter to a psychiatrist. I never did receive a reply.
More recently I let another typing error go unnoticed, I'd misspelt 'risible' on the Rabbit mugs - all of them.
Unfortunately they've been selling rather well, so I've been gainfully employed not only in correcting the error, but also in contacting the customers to arrange replacement. It's been a time-consuming lesson in proofreading and the results of not checking things thoroughly.
As you can see from the Rabbit of Death, the mugs are now all correct and once more ready for sale. Take a look at them at http://www.zazzle.com/arobooksworldwide/gifts?dp=252585008705651924 or http://www.zazzle.co.uk/arobooksworldwide/gifts?dp=252585008705651924 . Do let me know if you spot any mistakes!