Hi guys. Serious Sam 2, Serious Sam 3: BFE and other selected Sam titles are on sale right now. You can grab the game at 90% off it's regular price.
You can find more here:
http://store.steampowered.com/search/?snr=1_4_4__12&term=serious+sam
Offer ends on March 19th for Serious Sam 2 and on March 21st for all other Sam titles.
Enjoy!