John Scalzi is an hilarious writer and journaller, whose Bathroom Readers
and National Lampoon pieces are practically required reading. A couple years ago, he wrote a science fiction novel called "Old Man's War," which he serialized on his blog. My editor, Patrick Nielsen Hayden, read the book and decided to buy it for Tor books, and now it's available in hardcopy, with a starred Publisher's Weekly review, no less.
Old Man's War is a cross between Heinlein's Starship Troopers and Haldeman's Forever War -- a raunchy, action-packed, thought-provoking book about galactic-scale warfare where lightspeed lag and distant, unimaginable alien technology are central to the story.
In Old Man's War, senior citizens can enlist in the space army, and when they do, they are taken away and rejuvenated, using secret technology, given a turn in battle, and the survivors are retired to a distant world, never to see the Earth again. For a certain kind of person, this is infinitely preferable to certain senescence and death, and that's the sort of person that fills the pages of Old Man's War.
Scalzi's modern twists on SF classics are genuinely surprising -- I read this book in practically one sitting, but I keep going back to it now, thinking about the great ideas and writing. As a last minute Xmas gift, you can't go wrong. Here's the blurb I wrote for the cover:
Scalzi's written a dynamite, gripping and surpassingly original military novel here. It's Starship Troopers without the lectures. It's Forever War with better sex. It's funny, it's sad, and it's true.