We'll add your voice to the enhancement request to graphically show which hosts are alerting.
Just as an FYI, one way you can see which host is alerting is by turning on the tray icon popup message and including $host in the message someplace. That way, you can look at your tray to see which host most recenly fired the alert.
As for showing which alerts are associated with a specific target, this probably needs a bit of thought. Maybe if we let you pick your own letter when you create an alert, and then display that letter (or multiple letters, for multiple alerts)? Would it make sense to allow multiple characters here, and then the alert column could look something like this:
[>500, PL] (two alerts, comma separated)
[5%] (two alerts, single-character, no comma separation)
What makes sense here? Should we allow more than one character as an alert "abbreviation"? Does it make sense for *you* to pick your abbreviation? What characters should be allowed? Should duplicate labels be allowed?
Now, let's combine your two ideas a bit. How about if we let you pick two labels, one associated, but not in alert state, one for in alert state. That way, you could use "a" for not alerting, "A" for alerting (and b/B, c/C) or some combination of things like this. This does probably call for some kind of color too, though.
Any thoughts on this?
Thanks for the feedback!