ACS Wireless: @msg.acsalaska.com
Alltel: @message.alltel.com
AT&T Wireless: @mmode.com
Cellular One: @mobile.celloneusa.com
Cingular Wireless: @mobile.mycingular.com
Metro PCS: @mymetropcs.com
Nextel: @messaging.nextel.com
Qwest: @qwestmp.com
Sprint PCS: @messaging.sprintpcs.com
SunCom Wireless: @tms.suncom.com
T-Mobile: @tmomail.net
Unicel: @utext.com
US Cellular: @email.uscc.net
Verizon Pagers: @myairmail.com
Verizon Wireless: @vtext.com
Virgin Mobile: @vmobl.com
Bell Mobility Canada: @txt.bellmobility.ca
Fido Canada: @fido.ca
Rogers Canada: @pcs.rogers.com
Telus Canada: @msg.telus.com
Virgin Mobile Canada: @vmobile.ca
But how do I tell Mail to send a message (and how to format it)?