Making the Raspberry Pi Email IP on Boot

I needed my Raspberry Pi to email its IP address to me when it booted in order to ease finding the IP address when running headless.  Here's how I did it:

1. There are some really good instructions here: http://elinux.org/RPi_Email_IP_On_Boot_Debian
2. In order for it to work I had to set up an application password for gmail since I'm using two-factor authentication to login
3. Reboot and it sent me an email.  That was painless!