For those of you with Android devices. The Pro version of the Electrodroid Android app is on sale for 50% off.
LINKFor those that don't know what it is; it's a crazy useful electrical toolkit. It's basically a collection of tables, calculators, pin-outs, etc. all in an easily useable form. For example, it has a filter calculator, 555 calculator, a capacitor discharge calculator, resistor color code calculator, trace width calculator and the list goes on and on.