The game is a tad cheaper on Nuuvem, but some might not feel uncomfortable dealing with them (Greenman have improved this year), + there are probably more currency conversion fees on the Real than the US dollar.
http://www.nuuvem.com.br/produto/2403-sleeping-dogs-definiti...
The Nuuvem price expires in 23 hours.
Also on Greenman: The Dark Eye: Demonicon http://www.greenmangaming.com/s/au/en/pc/games/action/demoni... ~$6.30 US with the code
Serious Sam DoubleD ~$1.30 with code http://www.greenmangaming.com/s/au/en/pc/games/indie/serious...