The cheap PCBs, combined with the free "real" board layout software such as Diptrace and Eagle, and the incredible variety of parts available now like filters, oscillators, mixers, amplifiers, etc. make building things really easy. It seems too easy, sometimes. When I opened my first box from Itead, I looked at the boards for about ten minutes, confused, wondering how I ended up with ten PC Boards of my own design in less than two weeks for only $14 total. It seemed impossible. I guess I half expected them to take my money and have nothing show up.