“People are like toilets. All the good ones are taken, and the rest of them are full of crap.”
I stumbled onto this site of analogy examples and found some pretty entertaining ones, along with some enlightening ones as well.
“Life is like a coin. You can spend it any way you wish, but you can only spend it once.”
You can find more analogies here: http://www.analogyexamples.com/
At the top of the page, you’ll also find links to examples of metaphors, haikus, and a bunch of other stuff I’m too lazy to list here.