Apple has made it really easy for you to share files with colleagues if you are a .Mac subscriber. Your .mac Public folder can be accessed easily via any web browser. Simply entering the URL http://idisk.mac.com/membername-Public now produces a page that automatically includes download links for whatever is currently in your public folder.
Your friends and colleagues can also use your iDisk Public folder page to upload and share files themselves - make sure read/write is select in your .Mac preference pane.
If necessary, you can password-protect your public folder to limit access to your files.
Pretty cool, and pretty easy to use.