Where the hell did I put the remote control?
What do women want?
and
Why am I not on that list?
What is dark matter?
What is the nature of Cecil Adams?
Do parallel universes exist?
Creation or evolution?
Is there such a thing as reincarnation?
If time travel is invented in the future, has anyone from the future come back to their past (our “present”) to alter history?
We do know this one. The answer is “no”.
How many angels can dance on the head of a pin?
How many pins can you stick in the head of an angel?
Do we really have free will?
What killed the dinosaurs?
Is there such a thing as spirit (and, no, not the vodka kind!)?
What’ll we do when the oil runs out?
We know that one too. We’ll use hydrogen, ethenol and other fuels that we should have started using already.
This is also not as unknown as you might think. See this.
Mankind everywhere aspires to create societies in which life is fair, honest, loving and fulfilling. Mankind everywhere creates societies in which none of these things are true. Why? Especially given that we’ve had an awful lot of time to get it right.
What’s the weather going to be next Tuesday?
What did happen to Jimmy Hoffa?
The answer to this question.
Oh, wait… oops…
Who was Jack the Ripper?
How high is “up”?
Are you beautiful?
Is Leroy Nimod funny?
Who are tougher, the English or the Scots?
Why is Liv Tyler so hot?
Who is the Momma of us all?
Could God create a rock that was so heavy that even He couldn’t lift it?
Who made these shoes I’m wearing?
Why is that girl staring at me like that?
How did it come to be I’m wearing no trousers?
Why am I in this girls bed?
Why does she have a computer next to it?
Why is she wearing WWWE underpants?
Are they in fact my WWWE underpants?
Is she calling the police?
Have I broke into her apartment?
Am I wearing a Rex Harrison hat?
Why is Jimmy Hoffa’s naked body lying on the floor?
Is she a waiter?
Did I forget to put the cat out?
Well, they say if you have to explain a joke, it’s no longer a joke (*), but here goes…
You asked for “Things we just don’t know”, and I replied with:
“The answer to this question.”
which then answers the question, so it isn’t a “thing we just don’t know”, thus the “oops”. OK, so it was lame, sorry.
***** or more likely, never was
How to fix the spinal cord. 
I can answer that one. Because every once in a while someone will think they’re being clever and actually buy 10 packages of buns and eight packages of hotdogs.huge conspiracy…