Need a report to show me tickets that have been idle for xx days

Need a report to show me tickets that have been idle for xx days

I would like to know if there is a way to create a report that looks for any tickets that haven't been auctioned for a period of time, say 4 days, and notifys somone.
Note that I am specifically NOT referring to the SLA prompts Response, or Resolution.

A ticket may well be assigned to a tech, who then sits on his hands and does nothing with it for a few days. I want to know well before the 3 hours SLA clock in the dashboard comes around.

Thanks!

PS, can someone actually moderate and approve this post within a reasonable timeframe?