The following is taken from an ARRL ARES email newsletter. You can sign up for that here:
http://www.arrl.org/FandES/field/ares-el/
In order to receive email as text messages, send the email to the following address,
depending on your carrier. Check to determine which (if any) charges apply for SMS
messages on your phone contract.
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