my question: why? are you experimenting with other starch sources, or are you having problems reaching normal conversion in the mash?
I know of Beano, and I've seen many say "only when all else has failed and you think you might just have to throw the beer out anyways". it converts so much that hte beer is usually overly thin and dry since the non-fermentable sugars get broken down and fermented.
Primary: English Mild
On tap: Pale Ale, Lancelot's Wheat, English Brown Ale, Steam Beer, HoovNuts IPA
Bottled: MOAM, Braggot, Raspberry Melomel, Merlot, Apfelwein, Pyment, Sweet mead, Cabernet
Gal in 2009: 27, Gal in 2010: 34, Gal in 2011: 13, Gal in 2012: 10