As part of my homebrewing hobby, I started making limoncello last summer. A terrific warm weather addition to cocktails, but also great on its own as a digestivo.
The limoncello went so well, I decided to give a few other citrus fruits a go. First up, tangelos. While not an orange, they have a certain sweetness that's closer to that of an orange, but with a nice acidity that ties them to tangerines (of course) and also to lemons. Of course, there is sugar in limoncello (and tangelocello...has to be a better word), but I find both of these to be a terrific complement to bourbons, especially those w/high rye content. The current OGD BIB is a product that in particular seems to meld with both of these beverages (I prefer the ND OGD neat).
I have orangecello and blood orangecello in the pipeline. I'll report back on the results.