Gotta Dude Rollin. A male alternative to LOL. GDR or "Gotta Dude Rollin" is used to signify the actions that follow something that's funny. Which is uncontrollable fits of laughter causing one to roll on the ground laughing
Jimmy: "Yo mama so fat she goes to a restaurant, looks at the menu and says 'okay!'"
Timmy: "LMAO, GDR!! That was funny"