What happens when you get all the postcards on kingdom hearts?

I don't really remember what specific item you get after you've retrieved all 10 postcards, but I can tell you where to find them:

1. Use Blue Trinity Mark in 1st District of Traverse Town near the cafe

2. In blue safe near the door to the 2nd District (you can't get it until after you have Donald and Goofy in your party)

3. On the roof of the Accessory Shop (wait until you have the High Jump ability because it makes things easier)

4. Hit the fan in the Item Shop

5. Synthesis Shop - examine the poster on the left side of the fireplace

6. 2nd District - in the chest on the awning of "Boots & Shoes"

7. Gepetto's House - 1st District - check the shelf in the back left corner

8. 2nd District - Gizmo Shop - step on the three square switches then check the clock (you must use Thunder on the cord in the 3rd District before doing this)

9. 2nd District - Gizmo Shop - step on the three square switches then check the clock (you must use Thunder on the cord in the 3rd District before doing this)

10. 2nd District - climb the ladder behind the Gizmo Shop - jump across the rooftops until you find the window entrance to the 3rd District - the Postcard is hidden in the corner to your right