Open an account with Google (if you didn't so far), get gmail address and choose lifetime personal phone number. You will connect all your numbers altogether with easy management and making calls from your contact books, even abroad, from any computer or iPod touch. It's look even more promising, than Skype, which after last Apple's update simply refuse to open and aborting at each attempt to use it.

Skype on iPhone doesn't work, God knows why, even thru Wi-Fi. Even their own iPhone's headphones messed up, no telling about outside Bluetooth devices.

Google "pretend" to be people's servant, not ripping-off crook from side of the road.