Janis Joplin's Porsche could sell for $400,000 By: CNBC.com News September 15, 2015 at 12:32 PM EDT As part of its "Driven by Disruption" sale in December, RM Sotheby's is selling Joplin's colorfully painted 1965 Porsche 356C Cabriolet. Read More >> Related Stocks: Porsche Auto ADR Volkswagen A G ADR