> *At the end-of-day on Sunday, May 31st, the most-voted post will become the next [tag:community-challenge].* > > It is June 1, and the top-voted answer is: [**Decrypt a monoalphabetic substitution cipher**](https://codereview.meta.stackexchange.com/a/5330/31503) April's [Calculator submissions](http://codereview.stackexchange.com/questions/tagged/calculator) submissions are still rolling in, and May [Battleship submissions](http://codereview.stackexchange.com/search?q=battleship) are starting to arrive, but I felt it'd be prudent that we get a month's challenge decided early so that a challenge can be agreed upon before the month begins (just before). What should we do this time? Feel free to resubmit non-winning ideas from previous rounds, although new ideas are usually more successful. - Post an answer to this question with your challenge - Vote for those answers which interest you - At the end-of-day on Sunday, May 31st, the most-voted post will become the next [tag:community-challenge]. Once the challenge topic is decided, you can post questions on the main-site related to the challenge. The idea is to run the challenge all the way through June... although nothing stops you from posting an "entry" later than that :) Disclaimer: Most of this text is borrowed from [Mat's Mug](https://codereview.meta.stackexchange.com/q/5174/52915).