Yes, in Plus you not only can make your own custom categories, but there is no limit to how many you can make, and you can name them however you like. I do not use FB, but I do something similar with Leite's Culinaria. I save them to my category 2X or 3X, so I can try to enter them as much as allowed. Similarly, I save books, DVDs and CDs to categories such as Books Daily, or DVD daily.
You will be able to do this with FB sweeps. Also, in Plus, you will find the FB sweeps listed in their own category to start with (same with twitter and pinterest). And, you can still search and find them once they have expired.