Sometimes the most useful hacks are also the simplest ones. A case in point is the LED and resistor assembly that [Skippy] recently posted on his blog. The idea is to solder up some pre-made indica… ...

We have most of our beginning students trained to use a ‘current limiting’ breadboard wire that has a 270 Ohm resistor spliced in to keep the current draw under 20mA at 5V from the I/O pins.