If you have a porcelain sink, you must protect the surface from scratches and dings. Consider these options.
The standard for a porcelain sink protector is a rubber mat that fits on the bottom of your sink. They come in various sizes and colors. Some have suction cup devices to hold them in place; some have holes to allow easy removal.
Stainless Steel Rack
Stainless steel racks that look like a cooling rack for baking often sit upon little legs above the surface of the porcelain sink. The drawback is that the legs can scratch the sink and damage dishes.
This is a new and interesting product. It is made like the stainless steel rack, but it has a coating that continuously cleans your sink. They are especially nice for trendy white porcelain sinks.