Bell did not invent the telephone. At least that's the contention in The Telephone Gambit: Chasing Alexander Graham Bell's Secret, a new book by Seth Shulman. (The link in that sentence takes you to Amazon.com). The genius of Bell was in the ability to commercialize the telephone, which was really invented by Elisha Gray. Shulman came to the conclusion that Bell actually took a basic idea from Gray when he was reading Bell's 1875-76 notebooks and comparing them to Gray's papers. The Library of Congress only recently released these documents, now available online in high resolution. http://memory.loc.gov/ammem/bellhtml/bellhome.html
No matter how you feel about the controversy, the lesson is important. Commercialization is key. Look at Google. The Google guys didn't invent paid search. They just capitalized on it better than the originator. Overture, now owned by Yahoo! originated paid search. Google had to pay Yahoo! a license fee, after being sued by Overture for patent infringement. (They settled the suit out of court.)
If you're an inventor or are working with an inventor, get yourself allied with good marketing people. Figure out how you'll take your great technology and commercialize it. And don't waste precious time. Bell beat Gray to the patent office by minutes.