PagerDuty - Cloud based monitoring service
Guacamole - Access your computers from anywhere. Because the Guacamole client is an HTML5 web application, use of your computers is not tied to any one device or location. As long as you have access to a web browser, you have access to your machines.
OpsGenie - Alerting and On-Call Management for Dev&Ops Teams
Datadog - See metrics from all of your apps, tools & services in one place with Datadog's cloud monitoring as a service solution. Try it for free.
xMatters - xMatters transforms event data into intelligent communication IT teams, avoiding outages and disruptions
Warpgate Bastion - Smart SSH, HTTPS and MySQL bastion that needs no client-side software - GitHub - warp-tech/warpgate: Smart SSH, HTTPS and MySQL bastion that needs no client-side software