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.
Waybackpack - Download the entire Wayback Machine archive for a given URL
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
YouTube Decade - Watch the most viewed videos posted exactly 10 years ago
Better Uptime - We call you when your website goes down
ArchiveBox - The open-source, self-hosted internet archiving solution