I'm actually just about try this out.
Using shielded data cable should allow for using it as a four-mic snake, and as mentioned above, the ETS guys make a very handy breakout box.
I know there's someone else on here doing this, but forget who..
From a specifications perspective, the theory is that data cable is made for very exact transmission of frequencies way above audio signals so those big fat slow audio freqs should be just fine.
The twisted pair concept has been around since at least the dawn of analog telephones to reject external noise (common mode rejection), and that certainly is well proven. Adding the shield of course helps with running your mic cables along electrical power sources and makes it possible to run four channels of phantom..
I think enough people are doing this in real life now that its gotta work pretty well.
Belden (who I happen to deal with through work) makes many types of cables for all sorts of applications, including industrial stuff made to flex continuously:
http://www.belden.com/techdatas/english/7938A.pdfSome audio related info from Belden here:
http://www.sbe.org/sections/documents/UsingCat5e_Audio_Applications.pdfBottom line it should fun to check it out, and if I like it, it'll be a godsend for cheap, easy to manage, long mic cable runs