I've always liked the idea of one or two page 'cheat sheets' when developing. Although systems like concrete5 have a healthy amount of documentation on the web (in particular their API), it can be handy to have something physically in front of you to check function and variable names.
Over time I've scavenged a list of items for concrete5 that I have often used in development and from this list I've created a printable document. It is simply supposed to be a single page that can help you remember what is available and how it is used. Really obvious things have been omitted, leaving only features that (I feel) are regularly used, but are perhaps hard to remember.
Feel free to use it as you wish. If you have any suggestions (or corrections), please comment on this post.
Updates made: change to View::section, addition of View:url, removal of HOME_CID (it's always 1 anyway), addition of SITE, addition of EMAIL_ADDRESS_REGISTER_NOTIFICATION_FROM.