I'm not usually a gadget lover, especially in the kitchen. I prefer my tools to be multifunctional, but every once in a while I find a one use tool that make my life easier.
Cooking with cast iron pots and pans sometimes leaves me with a difficult clean up. Just recently I read about a great scrubber by OXO that seems to be made for cleaning cast iron. It's gentle enough to not ruin your pan's seasoned surface, but tough enough to scrub off stubborn cooked on food.
OXO is one of my favorite brands for kitchen tools because I have arthritis and this brand was originally developed for people with weak hands and problems gripping tools.
The bristles and scraper are plastic (nylon), but short and rigid. Perfect for those difficult scrubbing jobs. The handle is nice and thick to make it easy to grasp. Not expensive either; I will put a link below, so you can see the price.