I maintain a pretty wide net, much of which comprises film & design sites, which may not have much interest to you.

I’m into:

http://feeds.feedburner.com/CoudalFreshSignals
http://feeds.feedburner.com/TheThrillingWonderStory
http://jimray.tumblr.com/rss
Kottke
http://log.scifihifi.com/rss

Among some others.

Personally, I’ve gotten to know my students much better since I’ve started adding these random clips into my practice. They all assume I spend countless hours scouring the interwebs for these bits. However, I have a few secret weapons:

1. An RSS aggregator
2. http://www.notcot.org/
3. http://www.boingboing.net/
4. http://www.neatorama.com/

In addition to all the fun videos & pics, I swear I’ve found more sincerely educational content off these sites than any other three feeds I subscribe to.

http://www.yourvintage.com/yv/components/com_virtuemart/shop_image/product/a39895ccfd9c11f2338e2a980862ae5f.jpg

A bit harsh, but HIL-arious!

http://www.thetoque.com/040120/shatnercoin.htm

Re the queries from Alex and Glenn, in a two-hour block, we’ll spend twenty minutes crunching away at an an opener, after which I’ll show ’em a few photos. After our first instructional block, about halfway through, they get a five-min break and we watch a video.

If I had found a connection between math and emo Lincoln, believe me, I would have pimped it long before now. Do we discuss these afterwards? Share pieces of ourselves, our experiences, our opinions? Absolutely.

So while these are rarely mathematical, sometimes just entertaining, they are one of my best classroom management tools.

Whoops. I knew I wrote about this before. Maybe save me a moment, fellas, and read one of the show and tell posts.

Thanks!

All the metronomes are set to the same beats per minute, it’s just that they are started at different times. They are out of phase because that wooden table isn’t flexible enough to let the ‘nomes groove to the same rhythm. Putting the ‘nomes up on those cans lets them move. The board they are on rolls on the cans just slightly according to the average swing of the ‘nomes, bringing those behind the collective beat forward a touch and those ahead of the collective beat backward a touch. Pendulums allow that kind of flexibility (and that’s why some musicians swear by pendulum-based metronomes and curse electronic ones). Now that they are shaking together, they fall into sync because their pendulums can shift forward or backward just slightly, while still keeping the same BPM — you don’t notice micro-second shifts in beat. All the pendulums are moving toward the average rhythm, the collective beat, because of the movement of the board on the cans.

(1) Here’s the official physics paper on it: http://salt.uaa.alaska.edu/dept/metro.pdf
There’s no clippable quotation from that paper. And I don’t know even if I had the time I could tear through it. Maybe.

(2) Here’s the historical precedent — Huygen’s Clocks. http://www.physics.gatech.edu/schatz/clocks.html
From what I can get, this metronome thing is simply this clock experiment speeded up. So you see the synchronization faster.

(3) And wikipedia (love wikipedia) speaks about the phenomenon it here: http://en.wikipedia.org/wiki/Entrainment_(physics)

The relevant passage is: “The accepted explanation for this is that small amounts of energy are transferred between the two systems when they are out of phase in such a way as to produce negative feedback. As they assume a more stable phase relationship, the amounts of energy gradually reduce to zero.”

Which basically confirms what I thought when I first saw it: energy is transferred from one metronome to the other through the wooden base. The question is why the energy transfers in such a way as to create this “stable phase relationship” (synchronicity). But yeah – I think really working through that physics paper will be the only way to get that answer.