drag and drop to icon

[Eric S. Johansson]

I have a small problem that may be best solved by dragging and dropping 
a mail message to an icon.  But I'm honestly not sure what the data will 
look like from different e-mail clients.  Since most of my programming 
experience is something a user rarely sees, I'm not even sure where to 
start creating a test case.

I would appreciate pointers to documentation (and yes I did Google 
before asking) how to create an icon on a desktop (Macintosh and 
Windows) and have that icon act on something which has been dropped on it.

many thanks for any assistance

---eric