Inspired by the thread, I started examining my own trades from past years and found discoveries like these:
Yomi (sale date 30.5.2003) and a loss of 175 EUR (what could it have been?)
Turvatiimi (sale date 15.10.2003) and a loss of 5 euros
One that I owned until recently (but not continuously) and has been one of those holdings where I have always failed:
Teleste sale date 6.5.2002 (dividends 40 EUR) and a loss of 553 EUR
Saunalahti Group several sale dates 2002-2005 and a total balance of plus 1.4K EUR
Perlos several sale dates 2002-2006 (total dividends 202 EUR) and a total balance of minus 1429 EUR
Pohjola Pankki A sale date 12.4.2004 and a profit of 71 EUR
Pohjola-Yhtymä sale date 28.5.2004 (dividends 500 EUR) and a profit of 2.65K EUR
Hercules sale date 9.1.2004 and a loss of 140 EUR
Ixonos sale date 3.-10.1.2005 and a profit of 645 EUR
Nec Cp Adr NNM sale date 9.1.2004 and a loss of 31 EUR
Cramo sale date 14.6.2002 (dividend 180 EUR) and a loss of 48 EUR
Elcoteq sale dates 11.2.2005 / 27.4.2005 / 27.12.2006 (total dividends 1225 EUR) and a profit of 4.45K EUR
This is just a small part of eQ’s (eQ is a Finnish investment services company) trading balance from 2002-2008. My trading was quite active but small-scale, except for Nokia swing trades in 2002-2003, which were part of the market learning process, and I survived that session with dry feet (much turnover, little profit: sales 713K and purchases 711K). Fortunately, I understood to stop when I noticed “trading” becoming more difficult day by day.
From later Nordnet (a Nordic online broker) days, there are several other odd birds, but I will mention one more as I noticed yesterday that the company still exists and is still listed in Stockholm, with the closing price yesterday evening being 0.55 SEK:
Anoto Group sale date 24.3.2006 and a loss of 1.23K EUR (selling price somewhere around 16 SEK as a guess, held for just over 4 months)
I have traded a lot of different stocks over the years and I still have the energy, albeit much slower. 
Edit: That mysterious Yomi kept bothering me, so it seems it was some kind of setup related to Elisa (a Finnish telecommunications company):
»ELISA OYJ STOCK EXCHANGE RELEASE 29.3.2004 AT 8.00 AM YOMI MERGES WITH ELISA The boards of Elisa Oyj and Yomi Oyj have signed a merger plan, according to which Yomi will merge with Elisa. Yomi has been a subsidiary of Elisa since 2001, and the Elisa Group owns 51.46 percent of Yomi before the merger.«
2nd Edit: I can’t resist adding a few more investments, because when I chose these to put in my glass cabinet, for example, Elcoteq was included because I succeeded with it quite well relative to my stock wealth at the time, and Anoto because as an eternal bull, I have a bad habit of hanging on to weak branches and dropping strong ones too easily, as an eternal bull should. So with Anoto, I was able to let go of a terrible investment case, but it also took too long, but I avoided a catastrophe. The next case is similar to Elco:
Savosolar Sale date 29.8.2016 and a profit of 825 EUR.
and then the biggest single loss of my investment career with one stock:
Cellceutix Corp. Sales 08->11/2016 and a loss of 10.1K EUR
the company changed its name in 2017 → Innovation Pharmaceuticals Inc.
Innovation Pharmaceuticals Inc. sale date 8.12.2017 loss of 3.3K EUR total 13.4K EUR …I looked at yesterday’s closing price: $0.0479