I've heard of SIP phones and some sort of unlocked adapters I might need, but I'm not sure what to buy. I'll be heading abroad soon and will no longer be able to have my GrandCentral number call my apartment line, which is why I need to somehow configure a cordless phone that can work with Gizmo directly. I DO have an old Skype Box that used to do what I needed with the Skype software... can that be converted? Thanks!

The box I have is called a USB Telbox....