If you haven’t been keeping up with gaming news over the holidays, you may have missed the Steam store’s massive post-holiday sale.  Everything in their online store is on sale, particularly Valve games; if you haven’t played the Half-Life 2 series, the multiplayer masterpieces Teamfortress 2 and Left 4 Dead, or 2007’s best game Portal, then you don’t have much of an excuse not to get the complete Valve catalogue for 75$.  The incredible deals being offered here crystallizes my favorite part of the Steam Store: it isn’t static.  Bundles, weekly deals, free mods and demos have been offered throughout the stores lifetime.  My initial fear about online stores and digital distribution was the fact that their would no longer be a huge need for stores to sell things at a discount.  Their isn’t shelf space to worry about and exclusivity deals could easily bring in the necessary customers.  Valve appears to just enjoy rewarding its many fans by offering new deals every weekend (I grabbed the original Half Life for 99¢) and by adding new functionality to the Steam platform for free.  I myself am deciding between grabbing Multiwinia, the complete Civilization 4 series, and World of Goo; for 50$, I might just have to grab them all.