GAS Greetings and salutations GB Goodbye GBTW Get back to work GBU God bless you GD Good GD/R Grinning, ducking, and running GDR Grinning, ducking, and running GF Girl friend GFI Go for it GFN Gone for now GG Gotta Go GG Good Game (online gaming) GG Brother (Mandarin Chinese txt msgs...