Hellomyname Keyes

Hellomyname Keyes is an Easter Egg on the level Truth and Reconciliation in Halo: Combat Evolved, you will need to save your sniper rifle until you save Captain Keyes. Zoom in 10x and if you look closely at the name tag on Capt. Keyes, you will see above it, says HELLOMYNAME then below it KEYES.

Trivia

 * It is speculated that Bungie didn't have room to put the "is" in during the production process.
 * On the left of the badge (when facing it) you can see the Marathon symbol