The usage of "Following"

Is is proper in English to use this structure:

"The following is an example of a case where this applies."

In a lot of technical writing, especially from authors where ESL applies, I find them using above and below as adjectives, as well as "following" as a noun. I had always thought this was incorrect, but I am wondering if I am mistaken.

This usage, as RegDwight and Robusto has noted, is common, and is referred to as a substantive adjective. The missing noun can be obvious from context or intentionally left ambiguous in order to be more general.

Other common phrases that utilize it include ahem the following:

The good, the bad, and the ugly.

Out with the old, in with the new.

Only the good die young.