The heavyweight here is Kilogram, a free font from KalleGraphics. It is free for commercial as well as personal use.
I made the little graphic to show it off and I am enthusiastic about using it on a poster. Something to think about and work on over the next day or two.
I used the DropShadow effect in Photoshop for the word Kilogram itself, and no styling for the word font.
What do you think of the font?