Yep - in the Middle Ages in Britain, pepper was actually quite an expensive spice. However, to pay just one pepper corn (from which pepper is ground) was still a lot less than most rents, so the lease or agreement drawn up between friends, with one making a gift to the other for whatever reason, but to make it a truly legal contract, the rent was one pepper corn per year. Other commodities were used, as well, for the same reason, to ake a contract legally binding.

I'm immortal until proven otherwise