I have a sauce running now with ground cherries, peaches, scotch brains and trin seasoning peppers. Over the years I have used literally all kinds of stuff in my test batches; dragonfruit (really great when ripe - bulks up a sauce nicely), starfruit, jackfruit, papaya, passionfruit, figs, bitter melon, gooseberries, kumquat, lychee, quince, elderberries, persimmon, mullberries, etc. The only berry I really don't care for in sauce is strawberry as those seeds are a real b!tch to get out of the sauce after blending. Seedless strawberry jam though - pretty awesome.
Whenever I come across new stuff at the grocers I always buy a couple to taste them. And then I'm all like "I wonder what peppers would pair well with this in a hot sauce?"