The present invention implements an auction in which multiple types of goods may be auctioned in a dynamic process. Particularly effective inhibitor compositions are the natural amino acids cysteine and cystine and their decarboxylated analogues cysteamine and cystamine in combination with polyaspartic acid. The mixture includes a binder and a dry lubricant such as graphite, with a majority of the agglomerates having a shape that is generally spherical. methods and systems using the showerhead are also taught. The computer system compares the included IP address with the computer system’s assigned IP address and, when the two IP addresses match, the computer system activates a visual indicator proximate to the computer system. A cover is provided for hiding the learning sheet.