Visualping - Visualping is the easiest to use website checker, webpage change monitoring, website change detector and website change alert software of the web. Read more about Visualping.
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.
Wachete - Track web page changes and get notified. Free Sign-up. Have all data in one place
RPi-Monitor - RPi-Monitor is a tool that provides all the connected system peripherals properties and current metrics.
Distill Web Monitor - Distill is a web monitoring tool. It can monitor RSS feeds, a webpage or a part of webpage. Alerts in the form of pop-up, audio or emails can be received.
MenuBar Statistics - MenuBar Statistics is a lightweight app that sits quietly in your menu bar of macOS and displays computer information such as CPU, Disk, and Network, which is updated every 5 seconds.