Who else is using old cables/interconnects, and is happy?

Well I guess I have you all beat as far as age is concerned, bought 300 feet of Hartley Reference Cable (10 gauge) in 1980.  Spec'd  by Rich and custom built, Rich owns Hartley.  Needed 300 feet to get the 6 runs from amps to speakers in my tri-amped system.  As an aside very few people had speaker cables on their radar at the time.  Many people thought I was nuts, some still do.  And $300 for 300 feet was not a small sum (for me) at the time.  Yes, they are still in service.  I've inspected and re-terminated them as needed.
Regards,
barts

Still using my QED silver Anniversary bi wire cables. They sound good to me. Also have Audioquest type 4 (two 4 meter pair for each speaker) laying around somewhere. The type 4 is a highly regarded affordable cable and well reviewed by stereophile (stereophile recommended component for years). It is a neutral cable that just gets the job done. The QED cable is also a great affordable cable also well received. I can see why, as I have no plans on changing them out anytime soon. Priced the auditorium 23 cables (4 meter pair), over $1500! I would need 2 pair, ouch. Maybe someday.

Most expensive cable i own is my Audioquest thunder 2 meter power cable/chord. I think I paid about a thousand bucks. 

Oh yes, old stuff all throughout. 

Speakers : Straight Wire 'Waveguide' (using FuruTech spade and 30° angled screw tight banana type connectors).

Pre- to Poweramp : OLD versions of XLR Transparent MusicLink Ultra. 

LP to phono boards in Preamp : Vd Hul silver (something or other), 1,2 meters. 

CDP to Preamp : some old odd German brand low Oxygen type, 1' long only, XLR interconnects. 

CDP to DAC : OLD Transparent Reference, 2' long. 

DAC to Preamp : Some German brand, stock standard microphone XLR cables. 

Tried many, many alternatives but always preferred the lot mentioned above. 

I do concede that my system is just not sufficient Hi-End enough to make any noteworthy difference with more expensive / exotic type of interconnects and speaker cables. 😉
(also see my system page) 
Michélle 🇿🇦 

I also use Clear Day solid core solid silver speaker cables on the second rig. Took a few months to break in and open up fully. Bought them a few years before Paul passed away.

Phono cables are default Jelco JAC501. They seem fine. Better than an Audio Sensibilty cable I tried.
Interconnects are interesting. I’ve tried a few options with the best of intentions. While they all have had some nice aspects to the sound, they’ve all been colored in some way or another. So my trusty cheap ICs (not patch cords!) remain my reference for maximum detail. I use them for all non-phono connections in all systems.