Valve has started a “Perils of Summer” sale on Steam. It begins today and lasts until July 4th. We’re not sure what the specific savings are, but there are quite a few scattered across Steam. Valve has also reliably informed us that there will be special 1 day sales during “Perils of Summer”. The company seems to be making a lot of money from the service, but we’re not quite sure how after giving away so many copies of Portal and reducing prices/introducing free weekends.