Hyperping - Cheap uptime and performance monitoring with detailed reporting and flexible alerting
Domcomp - No-nonsense domain price comparisons, updated daily
Cronitor - Monitor cron jobs, micro-services, daemons and almost anything else, no setup required. Easier cron troubleshooting and no more silent failures.
Pricepeek - Compare prices of the same product across all Amazon locales
UptimeRobot App - Web, SSL, ports & Cron-jobs monitoring
dofo.com - Domain search platform Dofo.com gathers all registered (350 million) domains of the world in a single place. Dofo also brings together all the domain names that are on sale, provides useful features, all completely free.