1.to have a dirty bum(not exactly homeless) suddenly show up out of no where, annoy you and your friends, steal cigarette butts from the ashtray, and drink from used beer cans. Also to mooch everything they can ranging from food to weed to toilet paper and then ramble for hours on end talking about nothing but primarily a mixture of gibberish, pothead " ideas", stories that probably never happend especially about awesome or terrible experiences.
2. the appearance of an unwanted guest who doesn't get the hint to leave
A Shackteau is a humble, weather-beaten, structurally questionable shelter located in a spectacular or highly coveted place—Wales, Jackson Hole, Sun Valley, Crested Butte, coastal Maine, the Alps—where the building itself may be worth almost nothing, but the dirt, view, access, and mythology make it absurdly valuable.
In use:
Shackteâu - We thought it was an abandoned shed until the realtor called it a rare alpine Shackteâu with unobstructed views and listed it for $2 million.