Yes, you should definitely mail the envelope to yourself ... I agree. It's called a "Poor Man's Copyright."

Just be careful! Courts haven't been upholding these as much as in the past.

The idea is that since the post office is a division of the federal government, their date/time stamp is worth as much as that of the copyright office. In order to be absolutely sure that your copyright would hold up in court, take it directly into the postoffice, and ask the person to not only stamp the front, but also to place a stamp along the seal. That's you're safest bet!

************************************************** **********
Jenn Mattern
About.com - Consulting / Freelance Guide
Owner - J.H. Mattern Communications
Editor - AudioXposure.com