I was recently presented with an issue:
The organization I was working for was migrating from MOSS '07 to SharePoint Server 2010 and splitting up their massive web application into multiple web apps with many, many, many site collections. This organization wished to maintain a consistent experience when it came to search. Anyone who has configured search scopes knows that search scopes can be created at either the site collection level, or they can be created in Central Admin as a shared search scope. When it comes to displaying these scopes, however, they can only be configured at the site collection level by utilizing the "Display Group" container; There is, unfortunatly, no shared Display Groups.
So out comes PoSH!
The first problem I found was that using PoSH to add scopes to a display group, it was all to easy to add the same scope to a display group multiple times. It look a little work, but I got a ForEach loop written that checks each scope against the display group as it is added.
The second issue was that new site collections were going to be added by the support team on a semi-regular basis and they would to have these scopes added to them, so it needed to be easy to configure and flexable to use.
In short, I created a script that reads from an XML file and applies the display group to every site collection in a web application. That script is located Here