Need some indicators? We are big fans of these diffused green LEDs, as featured in the LoL shield. They are fairly bright so they can be seen in daytime, and from any angle. They go easily into a breadboard and will add that extra zing to your project.
Pack of 25 diffused green LEDs
3mm diameter
569-572nm wavelength
2.0-2.5V Forward Voltage, at 20mA current
100+ mcd typical brightness