Time Machine server

Under Snow Leopard, I used to share out a disk which was used as a Time Machine destination for others on the network. I can't see how to do that in Lion, unless I'm missing something?

I can see how to do it in Lion -Server-, but the app store reviews are rather putting me off - also with Mountain Lion being so close I'm not sure what the upgrade path would be. Has it now moved to become a server-only function?

Check out Proto the album: <http://studioicm.com/proto/>