I have to think about it, and get mixed up easily, which makes it really hard for me to give directions to someone who is driving. I'd rather just draw a map. If I have to give verbal directions, I prefer to use compass directions (which makes more sense anyhow- if you miss a turn and have to turn around and go back, it will still be north, but right and left are completely dependant on which way you're facing). I do have a very easy time reversing things, and when I was a kid, I used to write backwards sometimes- at first by accident, later on purpose. I have no problem reading things reflected in the mirror, although things written with backwards Rs or backwards Ns, like Tetris or Toys R Us or NIN, mess with me because it looks like it should be pronounced as Ya or Ee.
My grandma and my mom had problems with right and left too, and I don't think either of them had Asperger's. My grandma was a lightning calculator, and my mom was really good at doing math in her head too. My suspicion is that the right/left mixup thing isn't an Aspie trait, but that it is genetic and has some correlation with Asperger's.