The cost of spam is frightening, estimated to be approximately $130 billion each year. The tide of the daily spam is a continual thorn in the side for both providers and users. Spam is a waste of valuable network bandwidth, disk space and takes up users' valuable time to declutter their mailboxes.
To provide an insight into the quality of software that is available, we have compiled a list of 5 proficient open source Linux anti-spam tools. Each application warrants our highest recommendation.
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