"Knowing me, knowing yooou ...aahaaa" (ABBA song)
But you need LED's to see who you know, and plenty of them. So stack up!
Red, Green, Blue, here is the one LED to rule them all!

These 5mm units have four pins - Cathode is the longest pin. One for each color and a common cathode. Use this one LED for three status indicators or pulse width modulate all three and get mixed colors!

These LEDs are diffused; so they'll appear dimmer, but have a wider viewing angle.

Features:

• Forward Voltage (RGB): (2.0, 3.2, 3.2)V
• Max Forward Current (RGB): (20, 20, 20)mA
• Max Luminosity (RGB): (2800, 6500, 1200)mcd

Documents:

• Datasheet
• Wiring Example