I bought a couple of cheap phones with a Euro Sim card for traveling to Europe, it’s real basic, just for emergencies.
I use Vonage for my home phone service (VoIP). With that comes a free app which lets you use your cell phone as your home phone, anywhere where you have WiFi. Anywhere in the world, as long as I'm on WiFi, I can make and receive calls just as if I'm at home... it's very cool.