*** of course there is a catch.
- Unlocked iPhone
- "Three" prepaid 12GB MBB ($149 with 360 days expiry) & SIM
- Skype Online number ($80) (Optional)
- Jailbreak your iPhone
- 3G Unrestrictor ($2) from Cydia
- Backgrounder (free) from Cydia - get the 3.0+ version!!
- Skype Mobile (free) from Apple App Store
The Skype Online number is optional, but it allows me to divert my office desk phone (and any other phone) to my Skype account. Jailbreaking your phone is easy, but necessary to run 3G Unrestrictor which allows you to run wifi only apps over the 3G networks, and Backgrounder lets you run any app in the background, that way Skype is always available to take an incoming call.
With the Skype online number comes your voicemail, so you'll never miss a call anyway, with a notification being sent to your email account as well.
I'm using Call Credits, which is Skype's equivalent to pre-paid calls. Subscription plan also available, but make sure it suits your calling requirements.
You can receive incoming calls and SMSs on the mobile number assigned to the Three MBB SIM, but you'll not be able to make outgoing calls, but you can purchase SMS credits for the SIM.
If you are happy to just use Skype for outgoing calls and not have any voice mail, then you could save $80 and not get the online number.