I can't tell you the number of impulse buys I've made on Steam. Their weekend deals are typically very tempting and their holiday sales...well let's just say I spent more than I expected during Halloween. This weekend they have the
Codemasters Racing Bundle. It includes
Dirt 3 and
F1 2011, and with a 66% discount you get both games for $33.99. Not a bad deal if you're into realistic racing sims.
