Howie
Howard Cosell
Gregory Peck
Greggers
Gregor
Gerg
Greggy Tah*

*Mid ‘90s appellation.  Lasted the duration of the fame for one-hit wonder Geggy Tah and their catchy-yet-largely forgotten hit “Whoever You Are,” featuring the poetic lyrics “All I want to do is to thank you/Even though I don’t know who you are/You let me change lanes/When I was driving in my car.”

Greg the Egg
Greg the Great Grape Ape
Oreo*

*Working in a movie theater during college, the “G"s on my name tag were abnormally large and looked a lot like “O"s.  So patrons would lean forward and say “I’d like a medium-sized popcorn and a coke....OREO?” This carried over into being a camp counselor that summer: “OREO!  You’re on go-cart and canoe duty.”

Still in widespread use:
Greggles*

*Frequent email salutation from sibling unit Geoff.

Myson*

*Not really a nickname; email salutation used by maternal unit to address either son.  Also signs emails “Lovemom.” Meant to be affectionate and distinct, not an Orwellian neologism i.e. “plusmom,” “doubleplusmom.”

Greg Ho, a.k.a. HoHo*

*Used throughout place of work in order to distinguish me from company vice president Greg Hammond.

Dishonorable mention:
Ace*

*Attempted to claim this nickname in sixth grade on account of word sounding cool.  Ultimately aced nothing in sixth grade.  Nickname never caught on.