It depends on what you need in this moment. For schematic for SPICE simulations or for simple everyday usage OrCAD is good. When draw schematic for RF simulation it is better to draw it in simulation program. For b-diagram Visio when it is done for presentation and TurboCAD when for myself. For any mechanical drawings and when I need exact scale and high quality of the drawing I use TurboCAD. It is inexpensive (I paid about $50), but powerful program. And when it is necessary to have some plots I use Excel, MathCAD or Matlab depends on application. I also use USB digital microscope when I need to get picture of board, layout, chip and so on. It has up to 200 magnification rate (fine tunable) and allows to do the measurements across the picture. It is an excellent tool for PCB examination and our IC guys may use it for their chip related needs.