This is UptimeTwin watching well-known sites right now, with the same checks that watch customer sites: live response times, uptime over 24 hours, 7 and 30 days, and the real event log. No signup, no setup.
The line is each site's response time per check; the bars are its check history, tall and green is up. The board refreshes on its own every 20 seconds. Want this pointed at your sites?