Mathematica Home Edition's banner ad, revisited2009-02-07
It turns out to be very easy to remove the Mathematica Home Edition banner ad from all existing and newly-created notebooks. Just run this expression:
The effect of this command persists when you quit and restart Mathematica.
Something else you might find annoying is the "Welcome to Mathematica 7 Home Edition" window (the Mathematica Navigator), which appears every time you start Mathematica. You can prevent Mathematica from opening that window by running this expression: