Trigger method on timestamp

Hi everyone,
do you know how to make something happen at a specific timestamp? Specifically I'm thinking:

On our Express ECO form we have a field that lists the people who needs to be notified when the ECO is closed. At the same time we have a Change effective date, which may be some day in the future other than the ECO close date. When that date is reached I would like the system to email those needing notification and say 'Hey remember ECO-678346 we worked on three moths ago? Today is the day it takes effect.'

I am thinking some sort of scheduling service to run a server method???

Any input is welcome