They don't have the most exciting businesses, but they have a lot to offer nonetheless.Healthcare never sleeps. There is always demand for medical services, regardless of the state of the economy. Companies that offer these necessary goods and are innovative enough to keep up with the changing trends in the sector tend to last. That describes Johnson & Johnson (JNJ 0.12%) and Medtronic (MDT -0.15%) well. Both are among the largest healthcare companies in the world, have proven innovative abilities, and have ...