steam is free, you just need a half life or counterstrike cd key to play. if you need a cd key, you might be able to find half life or counter strike for as low as $10 at stores like walmart or target if they have them on clearance but i think the average price is like $20 so you might as well buy condition zero and use it to play CS online. www.gogamer.com has halflife and cs for $16 and cz for $20