What the hell kind of bugs are these?

Crabs.

Nanobots.

It is difficult to tell by your photos, but they might be ceratopogonidae or biting midges- sometimes referred to as Noseeums. http://en.wikipedia.org/wiki/Ceratopogonidae
Again, just a guess...

wood gnats?

My vote is with TimK...some type of midge. I think it's a water midge, though.

What's That Bug?

My vote is with Tamara- probably a water midge. I base this conclusion on Paul not having described a day of blood-feasting horror.

There was no biting, so yeah, I suppose it could have been water midges. The little buggers were so small it's hard to tell.

What made it so strange is that it was a one-night phenomena. They suddenly showed up in great numbers, and then were totally gone the next night.

Mayflies.

Definitely Mayflies - we've had the same scenario at our cabin.  They will pile up by anything left lit up overnight.

Here's a shot of the window sill, loaded with casualties.



It kind of looks like there are a variety of bugs there, but the tiny things resembling flies outnumber the random other stuff by a lot.

Ishy.  That's my vote.

I am going to barf

Definitely, midges.  They wrecked havoc on a ball game we were watching.  

Bugs disrupt Yankees-Indians in late innings

Crotch crickets.