A fresh cup mentions the Ruby on Rails exception notifier plugin. The idea is that every time an exception is raised in your code you get an email. This is such a horrible idea that I need to take the time to comment. As someone who spends all his time dealing with large deployments of software, email is the worst way of reporting errors I can think of. Think about it: Email is unreliable to deliver. It could get queued on the reporting server, a mail router on the network, or on your delivery server. Worse than that, it could get marked as spam, or randomly discarded. Email is expensive. There are two kinds of expense here -- email needs to be written to disk reliably, which means you sync() when you write the mail to a destination or a queue. For some MTAs, this can mean several syncs() per email as the mail moves between queues. There can be more than one of these MTAs on the way to the final delivery target as well. Additionally, storing email at the destination is expensive. Think of the backups, virus scanning, spam scanning, caching on clients and so forth. Email is…