Office challenge: Can you change the defaults for PowerPoint text boxes?

This week, show your PowerPoint prowess by showing us how to change defaults for text boxes.

You can change a presentation's slide master to set the default font type, size, and other properties for slides. However, you can't change these attributes for other objects, such as text boxes - or can you? Can you show a PowerPoint user an efficient way to change these attributes for a series of text boxes?