I need GNUPG to encrypt messages from my friends when we brainstorm ideas and inventions. So I use Thunderbird with Engimail I have Yahoo and Gmail accounts and

I need GNUPG to encrypt messages from my friends when we brainstorm ideas and inventions. So I use Thunderbird with Engimail I have Yahoo and Gmail accounts and set up message filters. I'd like to have a webmail address that does GNUPG on it, but the average user does not use encryption. Also I dislike having to give out my cell phone to verify because I get junk calls when they sell my info.