Changing the Approval Assignment Email Template dynamically within Approval Processes
Approval Processes in Salesforce are a great Administrator resource. They allow you to dynamically route an Account, Opportunity, or any Custom Object through for Approval from One or Many people.
Approval Steps can create Tasks, send Emails, and perform Field Updates on your records as they move through the process.
If you haven't used them before, I'd recommend you check out the Salesforce Trailhead module on Automation.