MailWasher works to let you block email before it gets to your computer. It does this by letting you preview all your email in your email accounts before the email gets to your computer. Additionally, Mailwasher will determine which of your email is spam and good so you can quickly scan your email, hit the 'Wash' button to delete the unwanted spam, newsletters and other junk so only the good email remains and is downloaded to your email program.
Sophisticated spam filters built in to Mailwasher help identify spam and good email, so you don't have to spend time wading through your email determing which is good and which is junk. The filters in Mailwasher range from a simple friends list and blacklist, through to external blacklists like RBL's and spam signature databases, though to custom filters which you can write yourself to block specific spam.
MailWasher is very easy to setup and use. It will import your email settings from your email program so you don't have to enter these, then show you a preview of your email waiting to be downloaded. You can mark any emails in Mailwasher which are not already marked as spam and then press 'Wash Mail' to remove the unwanted spam and the remaining good email is downloaded to your email program.