Add cream cheese, salt and pepper, and creme fraiche to make a mixture loose enough to pipe out into cucumber boats. Peel cucumbers and halve lengthwise. Slice cucumbers into 2-inch lengths. Use melon baller to scoop out the cucumber to make into small canoe-shapes. Spoon salmon mixture into pastry bag fitted with a with star tip, and pipe mixture into each cucumber "canoe." Top with a small amount of pineapple.
