Dragon,
You can't, the closest thing is to create a WordArt-object and format it so
that it follows the shape. In PPT 2003 use the Drawing toolbar and the
WordArt button, in the WordArt toolbar you will find a button to transform
the text. It may need some adjusting, you can use the littly diamond shaped
thingie and drag with it.
In PPT 2007, you can pretty much transform every textbox, just select the
textbox and on the format contextual tab click the text effect button in the
WordArt styles group choose transform and see if anything fits what you are
after.
You could also fake it by adding several textboxes and placing them in the
appropriate place.
