This appeared on the tree in the backyard this morning.
It looks like a honeycomb but little tiny octagons. The whole thing is about an inch and a half across.
What the heck is it???

I think you nailed it! The start of a Bee or Wasp structure.

Could it be eggs of some sort?

I'm sorry I actually have the wrong size on there. Its only 1/2 inch across, not an inch and a half.
I wish I could have gotten a better picture (camera wouldn't focus) as its much more bizarre looking in real life than the photo looks.
Bugguide.net identified it as a wheel bug nest!
These are actually great bugs as I've heard, they kill lots of garden pests. Apparently these bugs hitched on the bandwagon after the Japanese Stinkbugs which invaded the U.S. around 2000 and have been attacking all kinds of fruits/vegetables. The wheel bugs, are now preying on the stinkbugs. Bizarre critters.

Clip---> (the bumps on its back are actually water drops)
https://www.youtube.com/watch?...