I was born left-handed, but as Bernard noted, a lot of us were made to conform. I write, play guitar, hammer, use a hairbrush right-handed, but use garden and yard implements left-handed. There are many things I do left-handed because it is more comfortable.Someone asked about anyone who learned to play an instrument one way, then switched. I have a friend who is a true left-hander. He can't even think right-handed. But when he got a guitar as a teenager, he started to play it right-handed, then turned it upside down (as did Elizabeth Cotton), then, in his 30s, roomed with a guitar teacher who forced him to get a left-handed instrument and start all over. He is a good guitarist now and said he learned more in those first few months of left-hand playing than he had in the previous 15 or so years. Of course, I sure the teacher had a lot to do with it. But that is one success story about switching.
Here is a link to left-handed products. A Google search turned up more than 2100 hits for those terms.