Ruby allows you to use the ruby pawn (known as the old EveryPower pawn). It also allows you to use a jewel pattern in your name.
This power puts you higher on the visitors list than everyone else of your rank. See Topman article for more information about the ranking system.
Add (glow#0#jewel#ColorCode#rEffect) to your name. For a list of effects, see here.
You can also change the direction and angle that the jewel pattern moves in throughout your name:
For example: (glow#0#jewel#ffffff#r145) would result in a black jewel pattern rotated 145 degrees.
Note: You can use any color if you have Everypower. Otherwise, most colors are available but not green ones.