RoR useful gems or plugins

Hi,

google for it. Listing your installed plugins is a popular sport:

http://www.juixe.com/techknow/index.php/2006/07/05/top-11-rails-plugins/
http://blog.craz8.com/articles/2007/02/07/4-12-rails-plugins-i-use-in-every-project/
http://corkboardinc.com/blog/2007/03/15/rails-plugins-we-like/

The gem collection depends on the problems that you try to solve.
If we have a different problems than my collection will not be useful
to you.
You should get acquainted with all of them in general just to know to
pick the right ones.

One that I recommend in any case is ruby-debug for the obvious
reasons. :wink: