Martelli makes the high end rotary cutters, and they make a left-handed version. Most others can be set up both ways.
http://www.martellinotions.com/products.asp
Kai makes wonderful scissors, comparable to Ginghers in my opinion (at lower prices), and they make a couple in left-handed versions.
http://www.kaiscissors.com/category.php?category_id=50
I don't see any difference in rulers. Half the time when I pick one up, it's going the wrong way for my use at the time.