Forum OpenACS Q&A: looking for a way to know whether a package can be used site-wide

I'm planning on the overall site development for multiple subsites and subsites of subsites. How do I know which packages to install at the / level and use them throughout the entire site (i.e. bookmarks which i think is install once and use many places)?

It would be nice if the Software install pages reflected the differneces and only displayed appropriate packages...who knows maybe it already does.