timeago_helper.rb

# Render a timestamp suitable for javascript substitution (jquery.timeago)
# Sorry for copyright, I can't remember where I found this piece of code ! Do not hesitate to claim it

def timeago(time, options = {})
  options[:class] ||= "timeago"
  content_tag(:abbr, time.to_s, options.merge(:title => time.getutc.iso8601)) if time
end

# don't forget to add this to substitute times (HAML) :
# :javascript
#   $(document).ready(function() {
#     $('abbr[class*=timeago]').timeago();
#   });