Three Lego contraptions: conveyer, lift, & jigsaw

Any search for "contraption" on YouTube brings up a LOT of results involving what might be the ultimate contraption toy of modern times: LEGO.

Here we see some nice video (with music) of three contraptions:
1) Conveyor Belt
2) Lift and Dump
3) Jigsaw

Want more? OK! Here is a link to a whole bunch of Lego contraptions on YouTube.

If your aspirations are somewhat more modest, look into the book/kit Lego Crazy Action Contraptions. I haven't played with it myself, but gets truly outstanding reviews.

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