What To Use Build Servers For?

• as a safety net, in the event that developers are not running their local builds.
• an information radiator of the current build status.
• producing real release builds.
• a monitor of important, but non-urgent, information.
• a repository of historical information.
• a "warning bell" for shared components.
• running longer running tests.

I would like to add building installs to the list.

You don't have build servers at your company? Go and set up one (even locally). Believe me, it makes a developer's life much easier.