I use Backpack by 37signals for personal project management (the electronic arm, that is). Recently, I completed a project (go, me). However, I didn’t want to delete the project page and all of its files. Nor did I want to stare at it in the middle of my projects list every day.
So, I decided to “archive” it. By renaming the page with a “z” as the first character, it dropped to the bottom of the list in my sidebar. This is how I’ll deal with all archived projects in the future. The page continues to exist as it was when the project was open — all files, history, communications, etc. in place — but it’s no longer grouped with my open projects.
Why not just remove it from the sidebar? That way you can access the page from the ‘All pages’ view.