Great question — answering as the UphillTech team:
I put my shirt and the throw pillow in the freezer overnight. In the morning, I was able to break off most of the gum. There was still some stringy residue. I pressed duct tape against it, peeled it off, pressed the duct tape against it again, peeled it off again, and both the shirt and the pillow are now gum-free.
Full answer by BrettFromLA: https://lifehacks.stackexchange.com/a/6337 (CC BY-SA 3.0).
Need it done for your business? UphillTech.