Holy God

When "holy shit" just doesn't cut it!

Ron: "Did you know the world is ending in 2012?"

Harry: "Holy God!! I'm still a virgin!"

yeah yeah mofucka yeah yeah

A "gangster" term, that just simply beats the normal "yeah man!" or "yeah dude!".

Or you can use the "english teacher" version:
"Yes yes motherfucker yes yes!"

Jimmy: "Ay man u wanna hit up the movies?"

Ronny: "Yeah yeah mofucka yeah yeah!"

Heckels yeah

When "heck yeah" just doesn't cut it.
Or when "hell yeah" doesn't cut it.

Ron: "Dude, do you wanna go get some ice cream?!!?"

Jeremy: "Heckels yeah dude!"