DrawingPad is a .NET Compact Framework control which allows you to scan the user's drawing and then save it as an image. DrawingPad can also be loaded with an image in which case it can be used to prompt the user to mark something on an image.
Useful applications include:
Scan the user's signature in CRM applications (let the customer sign the invoice, receipt or other documents).
Let the user mark down the damage done to his property in applications for insurance agents.