A classic college dorm prank. A generous amount of urine is released into a plastic baggy, which is then sealed to prevent undesirable peepee leakage. The bag is then placed into a freezer just long enough to freeze into a solid sheet o' piss, at which point it is then ready to be utilized. The flat pancake shape of the piss ice allows it to easily be slid under a door, where it promptly melts and smells up the entire room with a hint o' piss.
"Yo I was sick of that dousche fuckin with my shit so i piss pancaked him hardcore. It smells like farm animal in his room now!"