Reusing Sponges

Oftentimes my sponges (with the scrubber tops) get gross pretty quickly from doing the dishes and it gets costly to keep throwing them out and getting new ones, so I've been recleaning them for reuse. I rinse them out and then place them on the top rack of the dishwasher. After running them through the dishwasher, most of the time, they come out looking like a brand new sponge. The sponges will stay pretty damp from the dishwasher, but if you leave it out, it can dry out. I've also placed them in the clothes washer and dryer before.