soaping
n.— «The guys stroll the streets in their Soap shoes, a brand of shoe that allows them to grind their way in a practice known as aggressive walking, or soaping. Their sneakers may not look different from anyone else’s, but their Soap shoes are fitted with a metal plate in the arch of the foot to allow them to slide across rails, ledges and other hard, smooth surfaces like an inline skater or skateboarder.» —“Caledonia teens use their shoes to grind out their niche in area skating scene” by Jayson Bussa Grand Rapids Press (Michigan) June 23, 2006. (source: Double-Tongued Dictionary)