I was going to come here and post inb4 bitttttcoooooonnnnneeeeeeeeeeeeeeeccccccccccccc....

But, in the days when BTC was about $350 USD, I had 10-12 BTC into program where they traded "arbitrage" between exchanges. Needless to say, they exit scammed and I lost it all. :D I can't remember the name of the site anymore, and I've flushed those memories from my mind.

So... not BTC, but a BTC HYIP (High Yield Investment Plan)

The only coin I ever truly regret buying was Vice. I refunded before the launch of their token, though, when I got banned from their telegram for questioning why their "github source code" was just a HTML wordpress template... and had no actual block chain code.

Arise Bank was another bad one for me, thanks SEC.