Between Horizons shows at full price for me.

Yeah, the window's closed on that one. It might be an idea to include the duration of the discount in future posts.

-90% Detective Gallo on GOG.com

It's  a buck fifty until the third of April!

edit: $1.64.

9 Noir Lives, which has a very strong 4.4 rating on GOG, is now 80% off, down to $4.
https://www.gog.com/en/game/nine_noir_lives

I know nothing about the game other than that it's a noir themed point and click about cats, but I bought it.