What are some alternatives?
When comparing Altospam and Malwarebytes Anti-Ransomware, you can also consider the following products
CryptoPrevent - CryptoPrevent is an Anti-Virus/Security Software Supplement, originally designed in late 2013.
RansomFree - Protect your PC from ransomware with multiple detection methods.
Scrollout F1 - Scrollout is a free and easy to use anti-spam email gateway designed for Linux & Windows administrators without advanced email security experience.
AppCheck Anti-Ransomware - Protect your PC with 100% Signatureless Anti-Ransomware AppCheck
Mailwasher - Over 8 million people use MailWasher as their spam filter
Bitdefender Anti-Ransomware - Bitdefender anti-malware researchers have released a new vaccine tool which can protect against known and possible future versions of the CTB-Locker, Locky and TeslaCrypt crypto ransomware families by exploiting flaws in their spreading methods.