Kind of a stupid thought, but what about the

I have give this line of thought some time myself.

So much of theory seems to be based on what life on earth presents. I see no reason to base all life in the universe on our local observations. How can we be sure that the universe is homogenious in this fashion. Given the universe's apparent size, seems likely our structure or form is only a small sample of what is possible, maybe even what actually exists.

Maybe, if people really have had contact, it is only with beings in the range of our stature. We might even miss the smaller ones.

All life in the universe evolves in much the same way... throughout. Look at the latest theories from the world's leading scientists and this is what they believe because of the laws that govern the universe as a whole. The universe is a BIG fishbowl and it's fish can only attain a certain size. Contrary to the wildest science fiction imaginings, all intelligent life would likely be about our size and have 2 eyes 2 arms and 2 legs...

Oh... and this is totally IMO.

I also think there is a possibility that life could evolve in outer space and maby even follow certain rules that carbon based life does not. Or living beings made out of energy like certain Star Trek aliens and I know what is really out there is far more different then we could ever imagine and thats what makes it so interesting!

Excellent question.

I think that a lifeform's size would be relevant to the size of their planet.

If we're talking about an interaction between humankind and giant/micro species, I would think such traveling beings that have mastered light speed, that is, to reduce their matter into a lesser form of mass, such as energy or light, would sure be able to reassemble their molecules to a preferred size.

Speaking of molecules — what if we were actually beyond microscopic? Like our universe resides in a subatomic particle and outside our subatomic particle there is a larger universe and another, and on the other side within the actual subatomic particles that we can see in our own universe there exsists a smaller universe and it's never ending larger and smaller. All universes make up subatomic particles that make up quarks that make up molecules that make up protons and neutrons that make up atoms that make up everything esle in the universe.

owch. my brain just crashd. gotta reboot.

This reminds me of a Twilight Zone episode where a woman living in a cabin alone was being attacked by tiny little (like up to her ankle) aliens with lazer gun things in spacesuits. At the end of the episode they show the "aliens'" spaceship and it had a USA flag on it heheh. So really the lady was a giant "alien" on another planet. Good ole twilight zone.