Sample Code Needed: Export mxd Data Frame using envelope of features

I need to export the contents within my data frame using a fishnet to define the envelope. I want to generate jpeg tiles (with world files) for each square (feature extent) within my fishnet. I also want to define the scale at which it exports the tiles, to insure that it centres each feature within the fishnet and zooms to a specific scale before exporting the jpeg.

What I'm trying to do is very similar to "Data Driven Pages" but for the "Data Frame" and NOT the "Layout View".

Any sample code, that would help me to get started would really help.

Regards