A klein bottle is a very interesting thing...and since there are places where you can easily learn about them, go here:

Click Me!

And then you can understand some of my analogies between Klein Bottles and life.  But first, look at the pretty picture...oooo
And now, not as if you really wanted to hear it,
Are a few reasons why life is like a klein bottle:
1.)  Few people know what it really is

2.)  It can only, truly, exist in a realm beyond our physical world (aka the 4th dimension, aka time...but really, to someone in 2 dimensions, something in 3 dimensions would appear to be like time, so in a way the 4th is just another dimension beyond us)

3.)  It's hard to understand (as you see above ;) )

4.)  In its true state it is continuous within itself, an unbreaking one sided surface that is "unbounded"

5.)  Our reality is in 3-dimensions, a klein bottle can only be "immersed" in 3, reality can only be immersed in life--certainly, reality does not fully express life.

6.)  It only has volume in 3-d, it can only hold matter in 3-d, in its true form it has no volume, like..well...it only holds our spirits.
By now you're either confused, in agreement, pissed off, or amazed at my stupidity.  Doesn't matter, pick a state of mind, and have a nice day....
Leptons and pions, mesons and bosons, baryons and fermions, muons and kaons...
these are the building blocks of my favorite things!