I'm addicted to watching Rube Goldberg machines, maybe because they represent the misspent effort that characterizes my life. Here are my thirteen favorites (there are, oh god, so many more on YouTube), including the classic Honda ad, a chain of chemical reactions, a machine in the forest, and a compilation of all those cute ones from the Japanese kids' show Pythagora Switch.

1. MythBusters
"What's the myth?" "We don't need a myth, it's Christmas."
Tools: Model train, Mentos and Coke, nutcracker, oven
Highlight: The flight of the cooked turkey

2. Pythagora Switch
In these clips from a Japanese TV show, a marble follows a route until it reveals the show title at the end. Then a chorus of kids sing "Pitagora Suitchi," or "Pythagora Switch."
Tools: Household objects
Highlight: The soundtrack

3. Voting Machine
A big political voting machine from the 2004 election. Its vote was later overturned by the courts.
Tools: Erector sets, mousetraps
Highlight: "Yeeargh!"

4. Japanese Contest
A televised competition with giant machines that use bowling balls, bedsheets, and an aquarium.
Tools: Toys
Highlight: Pouring hot water on ramen; chain of fire

5. Nintendo
A game-themed animated machine.
Tools: NES games
Highlight: Duck Hunt

6. Half-Life 2
A custom level of the video game that exploits its advanced physics engine. (An honorable mention uses a Rube Goldberg machine to kick a character in the ass).
Tools: Barrels, ramps, buckets and a watermelon
Highlight: A soldier shoots a standing character on sight; the victim becomes a domino in the machine.

7. Creme That Egg!
A household machine built to squish a Cadbury chocolate egg.
Tools: Paper towel rolls, sliding candle, mallet
Highlight: Tiny toy band with Klezmer music

8. Cog
Honda's famous ad for the Accord, using car parts to lower a ramp for the car.
Tools: Tools from the car; Garrison Keillor's voice (for better sound, view here)
Highlight: The water-sensitive windshield and crawling wipers — or the window mobile

9. Cog Parody
Same as above, with two dudes subbing for most of the machine. Advertised a British phone service.
Tools: Crazy exercisers
Highlight: Dance party

10. World's Most Amazing Trick Pool Shot
One shot drives dozens of billiard balls into holes.
Tools: Dominos, billiard balls
Highlight: French commentators

11. Tim Fort's Kinetic Art
A beautiful domino run with some surprises, built in an empty studio.
Tools: Dominos, matchsticks
Highlight: The unravelling paper roll

12. Chemical Reactions
An excerpt from a half-hour chain reaction, this clip uses loads of tricky geek science and wins "most preparation by someone who's not selling cars."
Tools: Lab equipment including sparklers, flames, oil and a folding ladder
Highlight: Flying ball of flame

13. Sticks And Stones
A natural Rube Goldberg machine built in the forest. I think at 0:47 I saw an Ewok.
Tools: Branches, ropes, stones and bell
Highlight: Spinning leaf whirligig