ThreeLetterPerson

Some people are so famous that they're known by their initials.

Examples:

• RMS (RichardStallman)
• ESR (EricRaymond)
• GLS (GuySteele)
• JMS (JohnMichaelStraczynski, creator of BabylonFive)
• GVR (GuidoVanRossum)
  • Factoid: GVR happens to be the dutch translation of BFG - the Big Friendly Giant, of RoaldDahl fame.
    • See MisuseOfFactoid
• JFK (JohnKennedy) (John Forbes Kerry also fits; but he's not referred to as "JFK")
• JFM (JamesMcGovern) Known enterprise architect blogger and industry thought leader
• FDR (Franklin Roosevelt)
• LBJ (LyndonBainesJohnson)
• MLK (Martin Luther King Jr.)
  • Wait, someone stole my initials? :) --MarnenLaibowKoser, 10 Dec 2012
• ken (KenThompson) - yes, it's his name, but he has been known as just "ken" for a long time.
• JWZ (JamieZawinski)

How about people who are well enough known as to be recognized by a single initial?

Like: Grouped initials (one per individual - as part of a representation)

• K&R (BrianKernighan & DennisRitchie) - Ritchie is also known as DMR
• RSA (RonRivest, AdiShamir and LeonardAdelman)
• AWK (AlfredAho, PeterWeinberger, BrianKernighan)

Single initial representing most notable person associated with that letter

• W (GeorgeBush [middle initial])
• M and Q (for you James Bond fans)
• T (Mr. T)
  • No relation to TOP, A.K.A. TopMind.
• U (floating abbreviationism referring to YOU)

Other people are famous, but are (for whatever reasons) never referred to by their initials. Some are lucky to have a rare first name that is used:

• LinusTorvalds
• WardCunningham
• RasmusLerdorf
• Sir Tim (i.e., TimBernersLee)

JuneZeroFive