Here is the list of ongoing sales for a couple of titles:
1. Sea Dogs: To each his own - base game + DLC 70% discount at gamersgate
Sea Dogs: To Each His Own
Sea Dogs: To Each His Own - The Caleuche
Sea Dogs: To Each His Own - The Final Lesson
2. Sea Dogs 75% disount at GOG
Sea Dogs -75% on GOG.com
3. Sea Dogs; Carribean Tales 50% discount at GOG
Sea Dogs: Caribbean Tales -50% on GOG.com
4. Sid Meier's Pirates 2004 75% discount at GOG
Sid Meier’s Pirates! -75% on GOG.com
The GOG discounts will end on 11 December 2016
The gamersgate promo might last a bit, as is part of the Christmas pre-sale.
So if you want any of the games for a rather more than decent price, go and grab them.
Feel free to add more sales when they come. Some people might be interested in replacing their discs with a digital copy at a decent price.
Hope this post will help someone.