We're running a website which enables users to download documents about our company, such as:
-wallpapers with the company logo.
-company logos in various flavours.
-media kits in pdf format.

Since these files are quite big in size (some reach 1MB), we no longer want them to be downloaded from our website directly as it's consuming our bandwidth. Accordingly we've been looking into document sharing services. For instance we found Scribd which could allow us to share pdf files, but not our wallpapers and logos which are in png format.

Is there a free service we can use for our users to reliably download any type of files we want to host? (ideally on a service which allows users to easily browse through our files).