John Scalzi's novel Old Man's War shows up every month in the GWC Book Club selection thread. We've yet to vote it in as book-of-the-month, but I suspect it's about to get a boost in the poll. Why? The great guys over at BoingBoing are reporting this morning that Scalzi and publisher Tor are offering 'War as a free download to promote Tor's new "scifi supersite."
You do have to cough up your email for Tor's list, but that's the kind of spam I can live with.