Design Two Simple Icons

For a file manager, I need two icons, one ‘folder’-icon and one ‘file-icon’. The specifications are:
* size: 25 x 25 pixels
* transparent background
* png file format
* style: Mac OS X

Of every icon, I need a copy in a second color. Hence, the total number of deliverables is 4.

I’m looking for creative, yet simple designs.

Thanks for bidding!