Speed Cream is a product made by Bones, a subsidiary of the Powell corporation. What it is (according to the box): "New Racing Formula Speed Cream is a blend of low viscosity, high speed lubricants that allow your precision bearings to roll faster and longer with less wear than ever before." It is the lubricant of choice for most skateboarders and inline skaters. It is sold in 1/2 oz. bottles (13 mL), for about $5.
Personal Experience: my skateboard was rolling pretty slowly at the end of the fall. So, over the winter, I cleaned my bearings with gasoline and then lubed them up with Speed Cream. On the first ride of the spring, after 15 feet of gentle decline on a relatively smooth road, I managed to roll for an extra 100-150 yards, without any sort of pushing. And I was moving rather quickly. This will be a fun spring.