Within Email Editor Rules, you can have the same source using any number of different templates. Jim2 will then randomly pick a template when sending. You can use this to randomly cycle through a number of templates that can advertise various offerings of your business.
First, create the templates you wish to use for the random templates.
On the ribbon, go to Email > Editor Rules.
Enter the information according to Editor Rules.
As you can see in the above image, as you add your sources and templates, hover over the Template field and a pop up will tell you that this template will be chosen randomly from amongst duplicate source rules as in the Templates by Report section (below).
Further information:
Create a Default Email Template