Although I can't imagine planting a blackberry (they are totally invasive in my neck of the woods), the thought of a thornless variety does sound inviting. I made a lovely jam last season by adding about a half cup of rum as I cooked down the blackberries, gave it the name 'Rumbleberry' for fun. Also added a bar of extra dark chocolate to raspberry jam, which also came out well. Both added subtle flavors. My co-worker gave me a jar of peach jam with added vanilla and ginger, very yummy. Fun to experiment.
