Scott,
There are options in the settings for ShowCase that allow you to restrict search by how many per row, per page, and also over time.
I'll also mention that you can create "Finders" that restrict search operations to a single or select set of showcase types. This is useful if you are wanting to share information between members. For example one of our customers is building a ATV Trail database that will be presented in the navbar as a separate type of search and display.
Mark