I ran across this awesome free monitoring service from UptimeRobot, and of course I couldn’t resist the temptation to add club6.nl and the other tildes to it. It checks for SSH (port 22/tcp) every 5 minutes.

Furthermore, using UptimeRobot’s API I created an external site at http://tilde.hol.es with a JSON/JSON-P data feed (thanks Hostinger!) Default output is JSON, but just add a callback URL param if you wish JSON-P output.

There’s an array with all tildes monitored. For each tilde, there’s an object like this:

{ "host": String, "code": Number, "status": String, "uptime": Number }

Friendly host name. Matches global domain, not SSH host (i.e. club6.nl vs tty.club6.nl)
Status code for the monitor>status key: 0 - paused, 1 - not checked yet, 2 - up, 8 - seems down, 9 - down
Friendly description of the code field above.
The uptime ratio of the monitor calculated since the monitor is created.