One of the best things about cheese it that it can easily be molded into log form -- and foods shaped like logs always mean that you're in for a good time. This version balances the nuttiness of Swiss and the pungency of blue with sweet dates and smoky bacon. If logs aren't your thing, you can always roll this into a ball; if you're absolutely no fun whatsoever, just serve it in a dip bowl.
Cut the bacon into 1/2-inch pieces and place in a cold skillet with 1/2 cup water. Turn the heat to high and cook, stirring occasionally, until the water has evaporated and the bacon bits are crispy. Pour the contents of the skillet into a bowl, reserving 2 tablespoons bacon grease in the skillet. Reduce the heat to medium, then add the onion and a pinch of salt and cook, stirring occasionally, until deep golden brown, 7 to 10 minutes. Turn off the heat and allow to cool completely.
Combine the cream cheese, blue cheese, Swiss cheese, chopped dates, port wine and onions in a food processor and pulse until smooth.
Lay two 18-inch pieces of plastic wrap side by side on the counter, overlapping by about 1 inch. Use a rubber spatula to scoop the cheese mixture into the center. Wet your hands slightly and shape into a rough log, then wrap firmly in plastic and roll a bit to firm up the shape. Twist the ends tightly closed and place in the refrigerator for at least 30 minutes.
Meanwhile, return the bacon and grease to the skillet over medium-low heat. Add the pecans and cook, stirring, until they become fragrant, then stir in a pinch of salt and remove from heat. Let cool completely.
Transfer the bacon/pecan mixture to a plate. Unwrap the cheese log and roll it in the bacon/pecan mixture to coat, pressing well to make the coating stick. Serve with crackers and mini toasts.