A thorn resistant tube (not slimed) patches just like any other.
After a nasty series of flats, I tried some brand or other of tire liners. I picked up a goat head, and it worked its way around the liner and into the tube. Fascinating! My current theory involves the puncture resistant tire. It seems like anything that lets a foreign object come in contact with the tube, of whatever design, is going to cause a flat.
Some people are like a Slinky ... not really good for anything, but you still can't help but smile when you shove them down the stairs.