I'm trying to create a trigger that allows the opportunity owner and the admin to be notified when there is no activity on an opportunity in 30 days. I tried creating a workflow that looked at the number of days since last activity, but workflows trigger when an opportunity is created or edited, and I need the field "Days Since Last Activity" to be looked at everyday. Is this possible to do using triggers?

I'm trying to create a trigger that allows the opportunity owner and the admin to be notified when there is no activity on an opportunity in 30 days. I tried creating a workflow that looked at the number of days since last activity, but workflows trigger when an opportunity is created or edited, and I need the field "Days Since Last Activity" to be looked at everyday. Is this possible to do using triggers?