The Discount Chooser Mega Module allows you to flexibly create product based (rather than dollars spent based) discounts with a built in admin panel. Somewhat less flexible than Big Chooser, but with the simplicity of point and click configuration.
Possible discounts include buy (some number of products), get (some number of products)
Products may be specified by product or category id, and category id can include any ancestor category (not just master categories id, but grandparent category, great-grandparent, etc.)
Please note: The name of this module was formerly Free Gift Chooser; it was changed to more accurately reflect its capabilities now that discounts other than 100% are supported.
For more information, please visit this product's webpage.