What's the most overrated or overpriced piece of equipment you own, have owned or come by?

I owned Bose 901 speakers for many years. I enjoyed them and experienced many hours of musical pleasure listening to them. They do not compete with truly accomplished speakers, but they are far from the disasters that they are often made out to be.

My biggest mistake was selling my Klipsch active SP-1 Speakers (free). And then I bought a new pair of Klipsch RP-280F. For €1000,-  $1140. The sound is better. Especially in the bass departement. My girlfriend hates the bigger look of the new speakers compared to the old ones. And for that amount of money i could easily have something better 2nd hand. A good friend payed $570 - €500 for a pair of Neat Acousitc Elite SE. No ear fatigue, great PRAT, WAF friendly, good treble. Damn i should have kept that money in my pocket for something like that at least.

Also another good friend didn't hear too much difference between my old and new speakers :( 

Most all software, 99% are usually bogged down with gimmicky updates and slower performance. Even peo DSP and VST effect I've bought or used seemed to be the same no matter how close they clams if emulates this or that, non of them are no match for hardware.  

2 Wavelength Audio USB DACs, the Brick and the Cosecant models. I owned pre-async versions so I don't know if the async versions represented a major improvement.

I have Aesthetix Callisto Eclipse with dual PS and remote control, total retail is USD 24K. I have never regretted purchasing it. :)