This isn't what I use bead chains for.

Somewhere, a shitload of empty cheap ballpoint pens are lying around not attached to desks.

This is great but his explanations of what's going on seem really weak.

I'm not good at explaining physical movement with words so I'm not going to try to spell it out in detail, but I think anyone who's messed with a bead chain much can figure out what's actually happening by looking at the video and keeping in mind that the links in those chains have a restricted range of motion relative to their neighbors but can rotate around their axis without restriction. What we're seeing is the loops the chain forms when it's in the beaker being pulled out straight, which causes some momentum of the links in directions other than the one the chain is traveling; the loop seems to be a result of the limited sideways (relative to the chain) motion available to the individual links, which could be tested by doing the same thing with a normal chain or piece of rope and seeing what happens. At least that's what I'm seeing. One thing's for sure, the shapes forming in the chain as it exits the beaker are definitely NOT because it's "hitting the side," and I submit as evidence the fact that it doesn't visibly hit the side once in the video.

It looks really cool though.

Hello, QA? I'd like to report a bug.