Rails Best Practices

to_s/to_s(:short)

override the to_s to make the method sensible instead of "display_name", "format_name"..

Use css sprite automatically

Using css sprite can reduce a large number of http requests, so it makes the web page loaded much faster. It it painful to composite a lot of images manually, do it automatically.

comment your magic codes

Ruby/Rails provides a lot of magic codes, especially for metaprogramming, they are powerful, less codes to implement more functions, but they are not intuition, you should write good comment for your magic codes.