Like other digital catalogues, even Humble Store currently has some offers dedicated to PC gamers. In particular, you can find on sale for a few hours the two games.
The first being Gunpoint, independent puzzle game that you can add to your digital library and save 75% of normal list price. To keep him company is instead the title pirate Tempest, which will sail the seas on Board of your virtual Galleonsspending 50% less than you would normally expect.

You can see our page at Gunpoint at this link, while the Tempest is available at this address.