Windows Home Server is designed to secure your data, so there's no supported way for you to do that using the provided interfaces. (You knew I'd say that, right? :) )
However, if you read through the
Windows Home Server SDK , you'll find
instructions for adding links to the home page , which users can see without logging in. You would need to create some sort of small web site of your own that would contain the files you want to expose. I don't believe you'll be able to serve them up out of your shares unfortunately, because you don't have anonymous IIS access to your shares.
There are other options. Whiist will let you crate a web site, or if you want the files to be in the shares, create a user that only has access to that one share and give that to your friends.
I'm not on the WHS team, I just post a lot. :)