One thing people generally hate is downloading a game and seeing either no readme or a completely useless one. The following is a general list of information that should be included in a readme. Keep in mind that this list isn't all inclusive, but is intended to make your life easier as a programmer. Of course, adding any other information that you see fit to be included is recommended, and strongly encouraged.

1. Be sure to name the file "readme."
2. A bit of info about what the program actually does. Be sure to include any limitations or restrictions this program may have.
3. Detailed instructions, including what files to send, shells needed (if any), any ungrouping needed, caveats (like L1-L6 must be unarchived), and key commands. Remember, the more you include, the less cluttered your email box and forums will be.
4. FAQs are nice.
5. All contributors to the files.
6. A list of kudos. Maybe let your local archiver (M) know his work is appreciated.
7. Version history is always useful, just make sure there ARE past versions.
8. Hints, cheats, and email addresses for those who are stuck.
9. Organization is very handy. Try to put in a table of contents, or at least different sections.
10. Humor can also be used to make it more enjoyable.
11. Also, a short disclaimer would be in order, declaring that you're not responsible for any damages, punishment, etc. that using your program may cause to the end user.