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In version 5.3 we added the "Status Filter" option to the admin area, which can be used to hide services, domains and addons in particular statuses. This is persistent so you only need to set it once.
Our blog post at the time describes this feature in detail: http://blog.whmcs.com/?t=86174

Products can also be marked as "Retired" which will hide them from the Products/Services dropdown menus, so they don't get in your way.

Then in version 6.0 we introduced the ability for customers to more easily filter domains and services lists, so with one click of the "View" filter they can view only the active services or domains.