Object-Oriented Design Patterns in CodeIgniter

[eluser]bluecarrot16[/eluser]
Alright. Yeah, I knew how to instantiate the class in PHP, I was just confused about the right way to load it in CodeIgniter. The "Helper or Plugin" part is what I was looking for. Considering the amount of hoop-jumping CI does in the Loader library (looked through the source the other day, just for kicks), I thought there must be a better answer than require_once()-ing in the middle of your controller somewhere. This will make the class globally available, yes?