Fridge: There are till a ton of condiments available. Sigh
I've been known to plan meals around maximum condiment usage.
Got lots of mustards? Honey mustard baked chicken!
Stirfry sauces are good for using up lots of random Asian-ish ingredients (sesame seed oil, chili sauces, hot sauces, oyster hoisin, fish, black bean)
Mayo? Time to make a couple of salads (egg, chicken, tuna) Also, you can sub some of the fats in baked goods with mayo as well. I'd google since I don't have any recipes to recommend. I do have vague recollections of someone in my family making "Mayo Chocolate Cake" which uses an ungodly amount.
Ketchup and/or BBQ sauce? Time for meatloaf! A squirt of ketchup is also good for balancing out the acid taste in tomato type sauce (since it is mostly sugar anyways)
Nut butter - Easy dairy-free milk (see my post above!)
Jams and sweet spreads - Can be stirred into yogurt, oatmeal, smoothies, tagines and curries. Anywhere you would like the sweet/fruit taste. My Grandma's secret to a good spaghetti sauce was a little dollop of grape jelly stirred into the sauce.
Umm...I'm probably forgetting some, if you list your condiments, I can probably come up with some ideas!