Sold with several different exterior designs, Case Logic's new Trend series of cases for iPod nano ($20), iPod classic ($25), and iPod touch ($30) are boring flip-closed designs that look better than some of their peers thanks to distinctive exteriors. The standard "Fitted Case" version, shown here for the iPod touch, is nothing more than plain artificial leather, but the "Satin Stripe" versions are available in three colors, with "Pop Flower" available…