Used as describing an object of dementification: looks weird, possibly tastes strange, maybe broken, not normal.
Can possibly freak small children out.
Tim: Hey Johnny, you're new pencil is kind of dementified.
Johnny: Yeah, my bro chewed it.
Tim: Erm....
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.