What are some alternatives?
EuropeanMX - Protects your company by blocking spam and virus before they reach your network.
Appriver - AppRiver is an email and web security company, develops SaaS-based anti-spam, hosted exchange, email encryption and web protection solutions.
SpamTitan - SpamTitan is an anti-spam email solution specifically developed to meet the demands of modern business. Delivering a spam detection rate over 99.9%
wynd - Shipping done for you
Altospam - Antispam and antivirus software on Cloud
Give Back Box - Reuse your Amazon shipping boxes to donate to Goodwill®