Spamihilator - The free Anti-Spam-Filter Spamihilator removes more than 98% of spam mails before they even get into your inbox.
ChatWhale - Gamify your customer communication and loyalty rewards
SpamAssassin - Use this program to "Unspam" your mailbox(es).
SendSMS.global - SMS Marketing Platform
Mailwasher - Over 8 million people use MailWasher as their spam filter
Open Loyalty for Startups - Open source stack for building customer focused products