This is a phrase used by a drunk or stoned person to have one more drink or toke to finish off the night. This way the persons night measures up to previous night of getting hammered.
Jimmy decided to have one more for good measure before he stumbled home from the bar.
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.