As I was doing some Contact Us forms, I realize that another good way to notify people is though, other then unreliable email, is SMS.
Some people use SMS, some people do not and will not - it's up to you and the client/relative/friend to talk about :)
Ok ok so here is a short list, for now, of email address endings for you:
T-Mobile: phonenumber@tmomail.net
Virgin Mobile: phonenumber@vmobl.com
Cingular: phonenumber@cingularme.com
Sprint: phonenumber@messaging.sprintpcs.com
Verizon: phonenumber@vtext.com
Nextel: phonenumber@messaging.nextel.com
where phonenumber = your 10 digit phone number
Found at this blog on TechRecipes: http://www.tech-recipes.com/rx/939/sms_email_cingular_nextel_sprint_tmobile_verizon_virgin