Is there anything better than driving through wine country, stopping off at a winery that you hadn't planned to visit, and discovering a gem? It's one of the wine world's great joys and it happened to me and Nena on our last day in the Finger Lakes a few weeks ago. As we drove up the western side of Cayuga Lake, we spotted a sign for Hosmer Winery. The winery we had planned to visit wasn't open yet, so we stopped in at Hosmer… and we're glad that we did. The wines impressed almost across the board. This was one…