One-page Esperanto reference guide
I found this link on the Esperanto subreddit. It features some useful basic vocabulary, the alphabet, numbers, verbs, affixes, pronouns and - my personal favorite - a really helpful correlatives table.
Note that it's only one page if you print it doublesided; I printed it on two separate pages to hang on the wall in front of my desk :)
When I was living in the San Francisco area & occasionally doing outreach for ELNA (now Esperanto-USA) we had this sheet to pass out to people. I still have several dozen in my files. There's also (somewhere) a sheet specifically for Science-Fiction fans & they were working on one for computer geeks. I wonder if they ever printed that?
Here is a Memrise course I'm finding useful to really drill them home: http://www.memrise.com/course/343142/all-the-correlatives-in-esperanto/
A bit late, but I found it here: https://esperantoreddit.files.wordpress.com/2016/09/1-page_handy-dandy.pdf