I'm a lefty and have no problems using a Kindle, like a few of the other posters here, I was actually quite glad to see that it had the page turn buttons on both sides of the device.
The joystick I only tend to really use when I am reading newspapers to skip through the articles quickly, otherwise I dont use it that much.
All that being said and just switching sides to join the off-topic discussion for a minute or two, when I was in junior school (6-11 yrs), a couple of the teachers there used to force me to write right-handed, I would get a smack if I didn't (this was in the days before the cane was made illegal), thankfully as I moved on through the classes and got other teachers, they left me alone to write left-handed. For a short while I could write with both hands "fluently", though these days I am predominately a lefty.
Otherwise on my laptop, I use my left or right hand on the trackpad, doesnt seem to matter, I mouse with my right but use my graphic table with my left. My right hand seems to be my brute force hand, I punch and throw with it, whereas my left hand is more precise and I use it when I need to be extremely cautious or delicate.
Btw, for those people who use left-handed scissors, did you know that you can get left-handed clocks too? I'd get one except for the fact it would drive my family nuts but my kids doctor has one