Does the length (resistivity) of an ethernet cable effect transfer speeds?

Length won't bother it. I assume you're talking about a coaxial cable, right? Google'd the topic to refresh my memory. I did remember that length didn't bother it, though. Here's a cleaned up snippette I snagged from a website. I cleaned out some useless stuff and clarified where needed:

Coaxial cable is a cable type used to carry radio signals, video signals, measurement signals and data signals. It exists because we can't run open-wire lines near metallic objects or bury it. In other words, trade signal loss for convenience and flexibility. Coaxial cable consists of an insulated ceter conductor which is covered with a shield. The signal is carried between the cable shield and the center conductor. This gives good shielding against noise from outside cable, keeps the signal well inside the cable and keeps cable characteristics stable.

Coaxial cable are usually grouped with the impedance and cable loss. The length has nothing to do with a coaxial cable impedance. For ordinary coaxial cable used at reasonable frequency, the characteristic impedance depends on the dimensions of the inner and outer conductors.

Jam it back in, in the dark.

o shit. Twisted Pairs. I remember soldering bundles of them (dunno much else about em) ;__; Not much fun... So many wires...

There's nowhere I can't reach.