There are some times when it's never good to get a phone call: dinner, after-hours, while you're in the shower. We can't do anything about that. There are other times when it's good to get a phone call: you slept past the alarm and you're about to be late, you just installed a new phone (does it work?), or you really need to get out of a bad date / movie / dinner with the in-laws. A times like these, you'll be glad you know about PhoneMyPhone.
The name pretty much says it all here. Just go the their website, enter your phone number, tell it how many times to call, and choose when to call—either now, or at some specific time in the future. Use it for a wake-up call, a reminder for meetings, or any other time when it would be handy to have the phone talk to you.
PhoneMyPhone is a free service.