The last couple weeks I've had an unusual inclination to hot dogs and I've eaten more than I probably should. I've been mixing it up with whatever I have in the refrigerator, and I've enjoyed them all.
Yellow mustard, ketchup, diced dill pickles (not relish). That's my conventional dog. I also like the variant with Head Country BBQ instead of ketchup and deli mustard in place of regular.
Homemade green salsa with Mexican blend cheese was really good.
Sweet thai chili sauce, cilantro, and diced cucumbers was even better.
All these on beef dogs, obviously.