Hows the craic?
Craic or CRACK is a term for fun, entertainment and enjoyable conversation - particularly prominent in Ireland. It is the freebase form of cocaine that can be smoked and is the most addictive form of cocaine.
It affects the brain chemistry of the 'enjoyer' giving a feeling of euphoria but after 5 minutes the dopermene levels drop off leaving the user feeling low and depressed with occasional full blown psychosis.