High as shit. A term used in conjunction with high as fuck. When you are so high that you get tired of the worn out phrase high as fuck, you might incorporate other profanity to substitute the word fuck, in search of some degree of originality amongst peers.
Good god, did I just take 5 bong rips of ghost train haze ? I feel like my brain is a sack of shit. I can't do anything right now.
"Danny, are you high as shit right now ?"
You say this to yourself and realize. You are high as shit.