You answered your own question.what specifically is the difference is an "anonymous account" vs just a regular hotmail account using something other than your name obviously? Flame away...
Its an additional (apart from your regular e-mail accounts e.g. work & personal) ON LINE e-mail account that you set up specifically for hobbying, that uses NO REFERENCE to your true identity. Its also best if you DON'T have your e-mail client retrieve the mail automatically for you- just in case you DO get an errant message at an inopportune time.