Originally released as a softback book with a campaign supplement that followed soon after Delta Green for me combined two elements I really love; the Cthlhu mythos and the conspiracy genre.  Where games like Dark Conspiracy and Conspiracy X both shine in their own niches, only Delta Green brought the mythos bang up to date.  It is a very different beast than Cthulhu Now which was the official modern day sourcebook for CoC and it taps into the idea that aliens have visited Earth using spaceships.

Now they are releasing a stand alone game which builds upon the work that has gone beforehand and it really does stand on the shoulders of giants.  There are various pledge levels available, enough to suit each persons pocket.