Everyone is excited when one come across any Easter egg. (Its other thing that Easter Eggs are not included with Microsoft products now for legal reasons) Here's one such Easter Egg, related to HP EX470/EX475 MediaSmart Home Server that allows you to change the behavior of the drive LEDs. 

So those running HP MediaSmart Home Server, just follow these steps to activate the Easter Egg:

-Launch the Home Server Console by double clicking on the tray icon.

-Hold down the Ctrl + Alt + Shift keys and click on the picture of the computer next to the LED brightness control.

-The control changes to "HP MediaSmart Server LED Light Show"

You can now select from the following options:

-Default System Lights-Holiday Lights (perfect for this time of year)-Descending Chasers (in blue, red or purple)-Ascending Chasers (in blue, red or purple)-Pulsing (in all colors)-Night Rider (in all colors)-Morse Code Credits (Yet to be decoded)

source: HP MediaSmart Home Server Easter Egg Channel10 HP EX470/EX475 MediaSmart Server Easter Egg (just in time for Xmas)