i'd just like to mention that cat5 does come in stranded which will not have the breaking problem that the solid core does. 1000 ft spindles can be had for around
$40 and also gives the ability to create custom network cable when nessecary. this amount of wire should be a liftime supply for most.
also i've used solid core cat5 several times with no problems(example-
here). the trick is to solder your connections. not for everybody i realize, but it works for me. i used this type of cable since i have a large amount left over from when i wired the house.
another option for the cheap bast@rd would be long parallel port or cintronnics type cable(i find these at suplus computer stores all the time for a buck). they contain large amounts of thin color coded wire that can be salvaged and the connectors can be used for detachable panels.