Austin Homebrew Supllies offers an option on all it's kits:

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> **1% Alcohol Boost:**  
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>  Add 1% alcohol to your beer without compromising its flavor. Brewvint Alcohol Boost is 55% maltose/45% glucose, a very fermentable mix with little flavor contribution.
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I'm curious about anyone's experiences with this. Does it really not affect flavor? Could I (theoretically) add several of these? Any other drawbacks to them?