What piece(s) of gear did you sell/give away that you would like to have back?


We've all done it - sold or traded a piece of gear we had fallen out of love with, then regretted that decision at some point. If you could go back in time, but could only retrieve one piece, what would that be?
discnik
My Tannoy Dual Gold 12 inches.... But they dont fit on my desk here and even in my next room when i will sell my house...

Happily it is not so much only the speakers quality that count, but the room where they are immersed like a whale in the sea...

Acoustical embeddings active and passive controls and material passive treatment weigh sometimes even more and at least weigh on par with the level of speakers design quality, i suppose  here that the speakers are not bad one sure...

Then my actual Mission Cyrus 781, a very good speaker but a notch under Tannoy, gives me tough a better sound than my Tannoy years ago, not because they are better like i said, but because they are rightly embedded acoustically, mechanically, and electrically....

The room is ALWAYS more powerful than any speaker and at the end always win....
Sold my Denon AU S-1 SUT year's ago! Been kicking myself for that bonehead move! 
Micro-sieke DD-40 TT with MA-505 arm. The most beautiful TT you ever saw. Solid rosewood base. Look it up online and check it out. Sold it for next-to-nothing 20 years ago because I thought vinyl was dead. Also sold about a thousand LP's for, I think, maybe a hundred bucks. Pretty dumb, you say?  Yes, it was.
Maybe these sales/gifts of favorite items led to good stereo karma in return?Anything occur afterwards that went in your favor which you didn't expect?