Erubis is an implementation of eRuby. It has the following features.

* Very fast, almost three times faster than ERB and even 10% faster than eruby
* Multi-language support (Ruby/PHP/C/Java/Scheme/Perl/Javascript)
* Auto escaping support
* Auto trimming spaces around '<% %>'
* Embedded pattern changeable (default '<% %>')
* Enable to handle Processing Instructions (PI) as embedded pattern
  (ex. '<?rb ... ?>')
* Context object available and easy to combine eRuby template with YAML datafile
* Print statement available
* Easy to extend and customize in subclass
* Ruby on Rails support

Erubis is implemented in pure Ruby.  It requires Ruby 1.8 or higher.
Erubis now supports Ruby 1.9.

Homepage:
http://www.kuwata-lab.com/erubis/
