Pingdom - With website monitoring from Pingdom you will be the first to know when your website is down. No installation required. 30-day free trial.
productboard - Beautiful and powerful product management.
UptimeRobot - Free Website Uptime Monitoring
FastNetMon - FastNetMon is a very fast DDoS analyzer with sflow/netflow/mirror support.
RapidSpike - RapidSpike is a reliability, performance and security monitoring service for transactional websites. Using next-generation synthetic monitoring & deeper than ever before data, RapidSpike is for businesses serious about protecting their online revenue
ProdPad - ProdPad helps your team gather ideas, surface the best ones and turn them into product specs, and then put it all on a product roadmap.