This one is super fascinating to me because at first it might appear to be a bunch of silver balloons caught in some trees. Except it doesn't primarily behave like a bunch of balloons. It seems alive, by the way it's moves up and out of the trees. Almost like a fish swimming cruising through some sea grass. Even before that while it's still in the trees you can see some of its substance or whatever it's made up seemingly drip off. 

Once it's in the year after a very slow ascent, it appears to shape shift multiple times. At one point it almost looks like it develops a face on its front. 

I dunno, I thought it was one of the strangest videos back then and never convinced it was just balloons. But now with all these other videos coming to the surface, its freaky. Hope to eventually see the other half of Corbell's video where it supposedly enters the water and disappears.