Hyperping - Cheap uptime and performance monitoring with detailed reporting and flexible alerting
Spamzilla - Spamzilla is a prevailing software for detecting many types of SEO spam automatically.
UptimeRobot - Free Website Uptime Monitoring
Expired Domains - Information about Expired Domain Names. Check the Availability of thousands of Expired Domains every day before they Drop and after. Just pick what you like!
UptimeRobot App - Web, SSL, ports & Cron-jobs monitoring
Domain Scout - Tools to help you discover great domain names for your projects.