The Rack Middleware/Metal screencast that they link to is actually really good. I hadn't delved at all into Rack or Metal before but I definitely understand the

The Rack Middleware/Metal screencast that they link to is actually really good. I hadn't delved at all into Rack or Metal before but I definitely understand their utility now... http://railslab.newrelic.com/2009/06/05/episode-14-rack-metal http://railslab.newrelic.com/2009/06/05/episode-14-rack-meta...