Skura Style Antimicrobial Polyurethane Sponges
I personally have been using these Skura Style Sponges for almost a year now and I will never go back to cellulose sponges.
The reason I love it so much is because it takes a lot for it to get that terrible "sponge smell." You know the one that stays on your hands, and doesn't go away even if you bleach the sponge? Not here.
I will say that it does occasionally get that smell, and when it does I soak it with a little water and throw it in the microwave for a minute. Voila! The smell is totally gone.
I store it in my Elevated Lifestyle Sponge Holder to make sure it dries, which helps further inhibit bacteria growth (the reason for the smell).
They estimate you'll need to change out your sponges every two weeks, but I used my first one for 7 months, and I could have continued to use it, but it was getting pretty ragged.