In light of Tuesday's announcement of the click-to-buy option heading to YouTube videos, it's worth mentioning Nintendo and YouTube's two-week old special promotional page for the Wii game Wario Land: Shake It. What makes it so special? It dynamically deteriorates based on what's happening in the video.
Coins explode out of the top of the player and trickle down the page, while various elements get knocked down with each headbutt, explosion, and power up. There's no way to regenerate items as they fall off without refreshing your page, although you can pick up each piece and throw it around, which is almost as much fun as watching it fall apart. Some things like the share and favorite buttons remain clickable too.
Useful if you were trying to read the video information while it flies off the screen? No. Mind-bogglingly cool and memorable? Definitely.