You might be able to write something in the content view using javascript in html mode which could do the ping for you. This only works to tell you if a server is up.
In the below example it looks it's hosting an image where if the server is up then it will serve that image. Otherwise it would get a broken link. You don't need to have all the javascript code either. A web image link to the server should work, I used to have a 1x1 pixel in a content view which sole purpose was to record how many people/ip address was accessing a said Omniscope report by looking at a Google analytics report of the link that the 1x1 was on.
Stack overflow has something more complex with AJAX which will return more detailed latency information but you may need some help from someone technical to set that up
If you refer to the PING command, Omniscope does not support PING. PING uses ICMP protocol. Daniel's suggestion will only work if the target runs an HTTP or FTP server.
This is fine for establishing whether a node is alive but the latency numbers relate to the round trip time from the remote server not from the machine hosting Omniscope.