I think with electronic stuff you can get real far because you can get it in bulk and you can make a lot of profit with it.
Also food is a bit too much a big company can do this but if you are just alone this is not gonna work in my opinion.
Just with the shortage of GPU's if you are close or have good ties with the manufacturer or suppliers, you will be earning good. Since law of supply and demand is implemented that will be good for the seller as it will bring you good profit. Food industry is also a good business.