Power cables oddly are probably the easiest to measure, since you can do a lot of it with a regular DVM.
Speaker cables and interconnects are harder, but I have a suggestion: rather than try to measure the cable itself, measure its effects on your system.
Place a microphone at the listening position and do a 20-20KHz sweep. Record the actual frequency response and distortion across the band. Then make the cable change and do the test again. A customer of mine did this for filter capacitor changes and was able to show that an improved filter capacitor resulted in lower distortion in his listening room. Some cables **seem** like they help certain systems play bass better; if that is really true you should be able to measure the results.
A lot of software is available that might allow you to do most of this using your laptop in the listening position.
Speaker cables and interconnects are harder, but I have a suggestion: rather than try to measure the cable itself, measure its effects on your system.
Place a microphone at the listening position and do a 20-20KHz sweep. Record the actual frequency response and distortion across the band. Then make the cable change and do the test again. A customer of mine did this for filter capacitor changes and was able to show that an improved filter capacitor resulted in lower distortion in his listening room. Some cables **seem** like they help certain systems play bass better; if that is really true you should be able to measure the results.
A lot of software is available that might allow you to do most of this using your laptop in the listening position.