MOSCOW, Idaho, May 1 -- The University of Idaho issued the following news release: * * * U of I inventors explore farm needs at ag expo * Matthew Swenson has a product. He also has a patent on that product. To learn how marketable his product is, without telling what it is, Swenson recently went undercover - sort of.  Swenson, an associate professor of engineering, was among a group of U of I researchers with patented products, or inventions in the process of seeking a patent, to attend t  more