Ruptime
This gives you the uptime and system load of shell servers.
centos7 up 7+03:34, 1 user, load 0.13, 0.06, 0.01 debian up 7+03:37, 9 users, load 1.15, 0.80, 0.67 ftp up 7+03:22, 0 users, load 67.00, 47.05, 42.75 mint up 7+03:38, 0 users, load 0.28, 0.37, 0.39 mxlinux up 7+03:34, 0 users, load 0.17, 0.16, 0.10 scientific7 up 7+03:31, 0 users, load 0.01, 0.03, 0.00 ubuntu up 7+03:50, 7 users, load 2.48, 2.98, 3.07 zorin up 7+03:35, 0 users, load 0.12, 0.14, 0.10