New cast-on I unvented yesterday. It’s stretchy, doesn’t require to estimate the length of the tail, and looks the same at both sides.

Using a crochet hook, make a slip knot, * a yarnover, wrap a yarn around the needle and pull through both loops; one loop on a hook; repeat from * until desired number of stitches minus one, and transfer the last loop from a hook onto a needle.
Note: It might be quite convenient to wrap the yarn around the needle clockwise and counterclockwise alternately, but always make a yarnover in the same direction.

In case of working in the round, cast on the required number of stitches, then transfer the last loop onto a needle and pass it over the first stitch to join the cast-on row.

Crappy drawing is for comparison JSSBO against ECCO.

P.S. They say, it’s the same as Chinese Waitress Cast-On. I agree on a final look, but my version is implemented kinda from the opposite side. And it’s about 10 times faster.
P.P.S. “Korean Programmer Cast-On”, hmmm?..