HarmoNESica? A brief refresher, then: it's what happens when you've got a copy of Super Tecmo Bowl, a Pocket Pal harmonica, and the desire to create a unique musical instrument. But if you don't have any of the aforementioned ingredients and just want the end result, eBay's got you covered as usual -- three HarmoNESicas have been gathering bids at the online auction house this week. Whether your pleasure be Dick Tracy, Super Mario Bros. 3 or The Legend of Zelda, there's a harmonica to match; and if (for some reason) you want to actually play one of the games, you'll find the ROM guts tastefully included. But before you make your bid, remember: there's more than one way to skin an NES cartridge.