One unusual sweetener used in baked goods and health foods is malt extract. A grain-based sweeter, it has a distinctively dark, molasses-like color and thick, viscous texture. Its flavor is much subtler than the richly acidic tang of molasses, which makes it a versatile and valuable addition to a wide variety of recipes. Malt extract isn't as readily available as many other sweeteners, so you may have to substitute another sweetener for it in recipes.
Sweet Southern Sorghum
In many ways, the sweetener most similar to malt extract is an old Southern favorite called sorghum. Sorghum is a grain closely related to millet, which grows prolifically even in hot climates and poor soils that don't favor higher-profile crops such as wheat and barley. Sorghum is much sweeter than malt extract, so use about half as much and adjust the rest of your liquid ingredients accordingly. It can be difficult to find sorghum in stores outside of the South, but it's available from online sources.
Brown and Mellow
Another grain-based substitute is brown rice syrup. It's readily available in supermarkets and health food stores; its relatively low glycemic index makes it suitable for those concerned with their blood sugar, including diabetics. It's similar to malt extract, and in fact some brands include some malt. Brown rice syrup isn't as sweet as malt extract, so it takes 1 1/3 cups to replace a cup of malt. Reduce the rest of your liquids accordingly when you make the substitution. Alternatively, you can use the same amount and enjoy a less sweet version of your recipe.
Add Some Refinement
The default substitution for malt extract in certain recipes is molasses, a byproduct of sugar refining, which is more readily available and similarly dark. Molasses is sweeter, so you'll only need about 2/3 cup to replace a full cup of malt extract. Molasses has a distinctive flavor that complements warm spices and dried fruits, so it's an excellent choice in some sweets. Unfortunately it can overwhelm more subtle flavors, so use it cautiously. Light "table" molasses has a milder flavor and lighter color than dark molasses, so it's often a better substitute.
Show Me the Honey
Honey is a liquid sweetener that can be included in a wide variety of baked goods and sweet treats. Like molasses, it's sweeter than malt syrup, so use 1/2 cup to 3/4 cup for every cup of malt your recipe calls for. Honey ranges from sweet-but-bland supermarket varieties to intensely flavorful small-batch products; choose one that's appropriate for your recipe. The variety that most resembles malt extract is buckwheat honey, which has a characteristically dark color and nutty flavor.