Walt wrote in rec.skiing.alpine:

Where do you get this? I've seen all-polypro rope, and Spectra with
polypro braided exterior, but not Dynema. Only 2 hits on the web for
"polypro Dynema rope", neither with substantial information.

WARNING: Boatnerd talk ahead - lubbers please avert your eyes.

I've been using Samson Ultralight, which is Polypro/Dynema SK-60 and
Yale Conception which is Polypro/Dynema SK-75. Conception is single
braid which means you can splice it, so I've been using it for
split-tail mainsheets. Ultralight is a Dynema core under a polypro
cover which makes it a PITA to splice, but it works well for anything
that doesn't need splicing. There are other choices as well.

You can get them from the usual suppliers, like APS.
http://www.apsltd.com/Tree/d3000/e846.asp

Plus they work great as thongs and string bikinis for spring [ob]skiing.

LOL. Thanks for the info Walt!

For whitewater boaters, looks like Yale Conception would make a great
throw-rope, while Samson Lite Speed would make a great rescue line.

Both are lighter than Spectra rope, and stronger than polypro rope.
The Samson Lite Speed actually has higher tensile strength than Spectra
of the same diameter.