Here's a quick meta point script that returns the number of hours (in decimal) since a point has last updated:

```
//returns the number of hours since the value (genset power) last changed
//get the current epoch
now = new Date().getTime();
//get the point's last timestamp epoch
then = p1117.time;
//get delta in milliseconds
delta = now - then;
//convert milliseconds to hours
hours = delta / 3600000
return hours;
```

This is useful if you want to know, for example, how many hours something has gone without running. It assumes that no new values on the points means the 'thing' isn't running, in my case I am looking at the output power of a gen-set to determine when it last ran.