The One Two by Four Chair 2011
It's common knowledge that 2x4s aren't actually 2x4. In fact, the dimension of a standard 2x4 is closer to 1 1/2 in x 3 1/2 in x 96 in. However, this is just enough material to produce a pretty nice chair. With these instructions, you can build a chair for about the price of a cup of coffee.
Download instructions here