Electronics Assistant

Nice App!

Electronics Assistant is a Windows program that performs electronics-related calculations. It includes a resistor colour code calculator, resistance, capacitance and power calculations and more. Details of calculations can be saved or printed. It provides all the functions found in the calculators section of this site and more in a stand-alone user friendly program.

http://www.electronics2000.co.uk/download.php#assistant

Wolfram Alpha is great with electrical calculations as well

http://www.wolframalpha.com/input/?i=300+ohms it'll show you the colours

http://www.wolframalpha.com/input/?i=5+volts+300+ohms automatic calculations

http://www.wolframalpha.com/input/?i=+30+amps+300+ohms another calculation

even filter time constants http://www.wolframalpha.com/input/?i=1+ohm+1+farad

and look http://www.wolframalpha.com/input/?i=1+ohm+2+farad+3+henry