You could create a contact card project.
The program could have the following features:
- Store contact information (such as name, address, phone number -- home/work/mobile --, e-mail address, fax number, and whatever you may want to add here). You can check on your phone what kind of contact information is stored there and you could create something similar.
- List the contacts.
- Store the contacts in persistent storage (e.g., in a file) so you can load them the next time you start the program.
- Share contact detail (export/import only one contact so you can give your contact to your friend and they can put it in their contact list)
- Add sorting (i.e., list them in a specific order, e.g. by the first name or by the last name or by phone number, etc)
- Add searching (i.e., to list only contacts that match specific requirements, e.g., the name matches specific patterns)
I tried to put them in dependency order, the bottom ones may depend on the top ones. Also, they tend to be harder towards the bottom.
Feel free to add your own feature to the little program.