Susan has done a wonderful series on women fighting in the Civil War. The History Channel has a 1-hour show on them, too. This is from their site:
In April 1861, the newly inaugurated President Lincoln calls for 75,000 men to fight for the Federal cause. What he does not anticipate is the shared desire by hundreds of women to fight for their country. Forbidden by laws of society, these determined women become the “Secret Soldiers of the Civil War.” Travel back in time and hear the story of two of the Civil War’s most interesting female soldiers–Sarah Emma Edmonds and Loreta Janeta Velazquez. Hear their tales of passion, recounting the sacrifice of identity, fear of discovery, and constant need for duplicity…even under fire.