I can really suggest Mozilla Thunderbird to anyone wishing to decrease the amount of spam in their mail boxes. The spam filtering capability of the Thunderbird is really good. It learns from what users you are sending e-mail to, and also it allows you to toggle a spam flag for incoming messages. Based on that it later sets the flags automaticaly, and if setup that way, it can delete unwanted messages itself. According to my testing, this e-mail client is much more faster than e.g. Outlook in processing e-mail and during the setup it can read and import the settings and messages from many other e-mai client agents including Outlook and Outlook Express.