Yesterday I read a technical document that was quite interesting but in which the author repeatedly used "principal" when he meant "principle"; so to help the author remember the difference, I came up with the following:
A law firm without principals has no managers.
A law firm without principles is typical.
Now, some of my best friends are lawyers, so I don't mean that quite seriously, but you have to admit that it is easy to remember!
Peter Saint-Andre > Journal