Vocaroo is a free service to record your voice and send it by e-mail.
It's quite easy, no need to install any software, just make your account and follow the directions, long in, record you message and send.
You can also embed it on your blog. oh, yeah, you need a microphone, and the person who got a mail also needs to log in to listen to the mail.
I'm wondering if I should send my voice message to one of my great friends, who lives in Canada and we haven't got any chances to communicate other than e-mail up to now. mmm