and they can be implemented almost identically in Javascript (just use 3.hours().ago() - each one can return a useful value, and have helper methods just like Ruby.)
It would be nice if js could rid of the keyword 'function' -- maybe make it a bit shorter like in coffeescript.
http://brendaneich.com/2011/01/harmony-of-my-dreams/ (He indicates that the function change will land in this ((very good)) podcast: http://www.aminutewithbrendan.com/pages/20110303)
3.times(#(){ $("#some_id").attr("href").hide(); });