Email to "managers / approvers" once a day instead of every time a record is submitted to them.

Hey guys - don't know if anyone can help me out with the following but thought I would give it a quick shot. I currently am firing an email off every single time a user submits a purchase request via our new web based system -- the user submits the request and boom, their manager recives an email giving a statement on the request, how much its for, and where they can go to edit it. Someone brought up that this is probably going to drive management nuts and to get it out and put some type of once a day summary email request in -- listing all the new requests that the manager has recived etc. Does anyone have any examples that I could use for something like this. Thanks - much appriciated in advance. Ryan ...