Over at Lifehacker.com they describe setting up iCal you text you with your reminders. This will really work well for someone who leaves your computer on all the time. Give this a try and tell us what you think.
First you have to make sure that you text e-mail is in Address Book. I am not sure what the domain is for anyones wireless provider except for Verizon. If you have Verizon then it is you 10 digit phone number @vztext.com.
Next set up the appointment you want iCal to text you about.
In the reminder field set it to e-mail and then select the mobile phone text address.
Set the time before and then you are set. iCal will send you a text.
WARNING: If you don’t have a text plan with you wireless carrier then you will have to pay for text messages.