You can basicly smoke any type of nut that you enjoy. Just google "recipe smoked nuts" wheras you can specify your specific nut choice.
Cold smoking is also good for cheese, sausage, fish, seafood, spices, salt, and so much more. It is important to keep in mind for food safety that meats and fish are usually cured before cold smoking to prevent food borne illnesses. Cureing also changes the clolr, texture, and flavor of the food (IE Cured Pork turns to Ham only when cured and smoked).
I cold smoke my hams and sausages before into the smoker itself to complete the smoking and cooking process.
There are so many recipes and sites available there are too many to list. Your best bet is to google your specific food.
Here is a basic starter from Bradley Cold Smoking Recipes
Although I prefer to use my A-Maze-N pellet smoker for cold smoking because the Treager Pellets are available locally without shipping fees and come in many varieties.
Let us know how you like the ProQ smoker.