This is a Timber Rattlesnake. They are highly venomous (reports of death from their bites have been reported). My husband whacked it on the head with a shovel, and he was stunned (that's when the picture was taken). He then whacked it on the head again to kill it because it was a threat to us. (If it's a nonvenomous snake like all the black racers we've found around here, we let it go on its way to kill all the rodents it wants, but venomous does not fly when you've got a kid.  Anyway, we of course had to see how big this sucker was:

So, yeah... This fucker was over 4 feet long, and FAT. This means he was probably full grown (Timbers only get between 3 and 5 feet in length). My husband still had him held with the shovel in case he wasn't fully dead (even though his head was flat, we like to take at least some precautions), but you can get a pretty good idea just how big that fucker was. Needless to say, we're now very paranoid about rattlers on our property. (PS:  Sorry about the spacing, I'm not sure how it got so fucked up.)