Many machines can be monitored remotely through data outputs as well. Our cell systems can be completely monitored by remote. It gives information on jobs run, tool life, machines alarms, current (and live) machine status,..... basically anything you "see" when you're at the machine less video.
Some machine tools as an option have web equipment you can integrate. This helps out quite a bit for tech service and what not. Still yet to be popularized but its "just around the corner".
For many of the older machines, you can use macros to output information from the machine as it runs with DPRINT. On the receiving end, there's software out there that can pool the info and email the bundle to where ever. Not exactly the most timely thing (not "live" anyway" since you have a lag for the data) but could be useful.
Also, many of the newer machines and controls that run in a Windows environment (or some other platforms similar) like Mazatrol, some Fanuc i series and such, can be networked to like a PC and use software like ReachOut or PCAnywhere to view the control.....