I assume you use Macintosh.

Do you want to be adventurous and bold? Try emacs for Mac!

Even more adventurous? There's vim (a vi clone) for MacOS. This is my preferred but be warned, it won't work as you expect, for sure! Vim has even got a Perl interface to extend its functionalities.

I suggest you to read tutorials for both editors, it's definitely worth it. Both editors have syntax highlighting and many many many useful features for programmers (e.g. go to the parenthesis that matches this one, autoindent and so on)

Think about being able to search and replace using regular expressions for example :-)

For more down to earth software (but less flexible and powerful for sure), have a look at the editors section in Tucows.

Happy editing!

-- TMTOWTDI