People that stacked AeroPress
It's hard to get a bad brew out of an Aeropress, and with a little tinkering and good beans it's pretty easy to get a great one. Just don't buy into the idea that you're getting espresso with only 1 bar of pressure (yes, even if you press on it really hard).
The most versatile coffee-maker I've used. While I prefer using specialised coffee makers for different coffees, aeropress is the only coffee maker that can do everything pretty well. It is also a must-have for me when Im travelling. Simple and easy to get a quick fix of coffee.