Better uptime is an uptime monitor service. It offers different alert methods and it also supports phone call alerts.

Testomato is a Czech uptime monitoring service. The tool can also check for common SEO problems.

Hyperping is an uptime monitoring and statuspage service.

Oh dear is an uptime monitor from Belgium. It offers status pages and many ways to be informed about problems. It also scans the whole site for broken links or mixed content.

Pingping is an uptime monitoring and statuspage service based in Germany.

Statuspal is a uptime montioring service from Germany. They offer statuspages (public and private) and performance metrics.