Wow, that's great! I just saw that you can have updates to your phone/email. I singed up for Janines package. It's a great tool!
I mailed one package in a small bubble envelope and then I mailed another package the next day in a 8x10 envelope that they told me would be best. I asked for delivery confirmation, they said I couldn't track her package.
I think I may have to start using another Post Office!