27 Letters

I thought of a sure way to become famous and add some breadth to the English speaking world.  If I could come up with an acceptable 27th letter to the alphabet it would get me into the history books.  We assume that we have all the letters we need.  But isn't it possible that there are pronunciations that we are over looking because we are missing a letter?  After choosing the letter, there must be a sound that accompanies it, and there would than be new words that could be made, each of which would need to have their own definition.  People would need to start using those words, having the ability to type the letter, and gradually the new letter and words would be accepted into dictionaries and the like.  I see adding to the alphabet as somewhat the same as adding more endings to internet addresses.  We started with .com, .net, and .org but now there is .info, .biz, and .tv.  Why can't we add to the alphabet?  Are we missing an opportunity here?  Why limit ourselves?  Why stop with 26?