UTP isn't a type of cable, it stands for Unshielded Twisted Pair. Catagory 5, which is most likely which he is refering to, is a type of UTP. Catagory 5 is made up for 4 pairs of generally solid core wire, which each pair twisting around each other. It shouldn't be that brittle, unless you have poor cable.
Cat 5/6 UTP makes a great interconnect, just using one pair. It also makes a great speaker cable, braiding some lengths together if you need the current capacity.
The best cheap I/C I've found is 32ga or smaller magnet wire, simply twisted together for unbalanced, or braided for balanced. You can also get teflon coated "wire wrip wire" from lots of vendors very cheaply and use this in the same way.
Being unsheilded, thay may not be the best in situations where there is a lot of RFI or hum fields, where a shielded cable might be better. Generally, I find shielded cables to sound worse, all else being equal.
You can get a three pack assortment at Radio Shack for about $4.00 which includes a 200 foot roll of 30 gauge.
It's a bit tedious to braid and terminate but I've found it more than worth it in the end.
You do have to be a bit careful with it though. I'm not aware of any RCAs or XLRs that have the collet type chuck strain relief of the Redels so you'll have to take some precautions there.
The four wire braid forms what amounts to two interwoven twisted pairs each at 90 degrees to each other. Tie together one wire from one of those pairs to one wire from the other pair to form one conductor and the same for the other.
I would say that if you're to use just one pair, make sure you ground the other 3 pairs, I would think. You can also use STP, shielded twisted pair, which is used for Ethernet/Token Ring generally so it also is fairly common.
I once tried a CAT5 braid (after reading rave reviews all over the internet) as a speaker cable. My Adcom GFA 535 II went crazy (even though the clipping lights won't light up I could hear strange distortion). By the time I realized what was going on I had a blown tweeter on hand
Finally I settled down with thermostat cable (available at Home Depot). It has 4 or 6 solid core individually insulated 18 gauge copper wire in a cable. The wires are not twisted hence capacitance is low. Cable with 6 wires give better bass, but I like the overall sound of 4 wire cable better. As opposed to 18 gauge zip cord the differences are subtle: better bass and more clear midrange. Might be just because I have been using them un-terminated and you can tighten the connectors better on solid core wires as opposed to multistranded cable (just a better connection).
As far as interconnects are concerned, I have read that capacitance is very bad, and twisted pair gives you quite a lot of it. Hence a parallel run of magnet wire is supposed to be best. Offcourse this arrangement is not good for noise cancellation and may not work very well in noisy environment (sheilding?). I have not tried different interconnects yet since my system is lower end. I will play with them once I have ZenV4 up and running
There is an excellent articale by Nelson Pass on speaker cables: