I really like the Avid "Tri Dangle" cable hanger- which is pretty much the same as the regular Tektro triangle cable hanger.
I'm not so much of a fan of the old "claw" ones- nothing particularly wrong- they're just so... ...common.
The roller ones... Rene Herse used them, so that counts for something, but I have 2 different DiaCompe ones in use- the one with the quick release built in and one without a quick release. I've gotten kind of sketchy about the QR levers- if it somehow gets bumped- there go your brakes.
My personal favorite it is the Spooky "Light Eccentric Adaptor." Is there anything particularly special about it? No. It's difficult to set up and it doesn't do anything special, but it looks really cool.
A few years ago, everyone was using the word "grail" to describe something they liked... so here was a 'grail cable hanger' thread:
Grail Straddle Cable Yokes!