Can I get some help with similes?

I have some homework for my English cl, we're writing similes. Most of them were easy. My favorite so far is probably 'Soda is like a bunch of Altos, if you leave them alone for long enough, they'll be flat.' And by the way, I sing Alto, so I know from experience. Anyway, I've been trying to think of a simile for 'The letter Z is like...' and I just haven't come up with one. Any ideas? Please? Thank you. Good bye.