The "country folk" version of "have a cow":
Your dad owns a dairy farm, so when Mom and Pop go out for dinner, you go out into the barn with a can of aerosol whip cream and spray it on your naked boner so one of the calves will suck you off.
CLYDE: Hey, Enos, are you going to the prom?
ENOS: No, all the chicks I asked turned me down. I think I'll just kill myself!
CLYDE: Come on man, it's not THAT bad -- have a cow!