I cull two extraordinary syndicated-comic-strip sites, http://www.gocomics.com and http://dailyink.com/, regularly for theater-themed comics. As always, I highly recommend subscribing to these superb sites.
Here are five Shakespeare-specific strips: Paul Johnson’ Fort Knox, Bassett & Harrell’s Adam@Home, Jan Eliot’s Stone Soup, The Lost Bear by Bradley Trevor Greive and the inimitable Shannon Wheeler’s Too Much Coffee Man. (I once had the pleasure of running Wheeler’s strips in the New Haven Advocate when I was an editor there, and met him in person at a comics conference at Southern Connecticut State University. Alas, the subject of Richard III on the toilet did not arise.)