Batch Watermarker is a powerful tool that helps you create watermark/overlay to protect your intellectual properties. Batch Watermarker can add watermarks (either image, text, or both) onto your graphic files in batches.
Dotfuscator Professional Edition is a .Net Obfuscator, Compactor and Watermarker that helps protect programs against reverse engineering while making them smaller and more efficient. The .NET obfuscation code protection tool selected by Microsoft.
WatermarkIt protects your images and photos by adding visible watermarks to them before you publish them. Watermarks are blended and integrated in images and therefore will replace (in a transparent way if you choose) some parts of your original image.