When discussing performance with colleagues, teaching, sending a bug report or searching for guidance on mailing lists and here on SO, a [reproducible example][1] is often asked and always helpful.

What are your tips for creating an excellent example?  
How do you paste data structures from [tag:r] in a text format?  
What other information should you include?

Are there other tricks in addition to using `dput()`, `dump()` or `structure()`?  
When should you include `library()` or `require()` statements?  
Which reserved words should one avoid, in addition to `c`, `df`, `data`, etc?

**How does one make a great [tag:r] reproducible example?**

  [1]: http://stackoverflow.com/help/mcve