I don't think there is one. I personally think that it will be better to try to live without it that search for a substitution that will keep you forever remembering that sweet taste and keep you always hard-wired to sugar. Also sweet is very craving promoting and will probably ruin any dieting plan/healthy lifestyle.
I don't really understand why people needs so badly sugar in everything. I mean, I like it a lot although I know it's pure evil, and I admit some things are difficult to be free of that sweet taste, such as sweets, cookies or the kind. But as for coffee, tea, yoghurt and that kind of things... do people take them without actually liking them so that they need to sweeten them so much? I have even found that cocoa may be nice even when full organic non-sweetened. Maybe it's something you start appreciating with time (and sugar detox most likely).
But, if one ever wants to experience the joy of that sweet taste, I'd go with the most natural sources possible: fruit, dates, raisins and maybe a little bit of honey, in small amounts. That should do the trick while being still pretty healthy sources or at least with a good deal of nutrients to question the possible drawback of an insulin promoting food.
Depends on yoy paleo philosophy.... traditionally brown sugar is 4 cups granular sugar to about 1/4 c molasses. I would just substitute your granular sugar of choice and use black strap molasses. Black strap does have a much stronger taste so you might want to start with less and taste and add until you get a blend you like.
Depends in your paleo philosophy. I would mix a granular sugar with either molasses or black strap molasses. Standard ratio is 4 cups granular to 1/4 cup molasses but mix it to your taste.
You can puree dates into a paste that works fairly well for substituting in baked goods. Honey tends to add too much liquid. (Soak the dates in water for a few hours, then process in blender or food processor).
coconut palm sugar is what id use if i HAD to use a sugar like sweetener, if anything gram for gram its even sweeter than sugar, low GI etc...
But if you have to... Heres a page with ideas and conversions. http://www.organicspark.com/portfolio/technique-how-i-replace-white-sugar/