Hi everyone,
some might already know it (it has been online for a while now) but those who don't I'd like to invite to have a look at sitemeer.com.
Sitemeer basically verifies whether a given service is online and reachable. It is similar to the is-it-just-me sites but comes with broader protocol support, full IDN compatibility as well as details about the connection.
The script itself is currently not open-sourced but might be in the future. There are also further additions planned, so feature suggestions are naturally more than welcome :)
Site: http://www.sitemeer.com
Facebook: http://www.facebook.com/sitemeer