I have a simple American wheat recipe (basically the Bluemoon clone recipe from HBT forum) which lends itself very well to fruit additions in secondary. So far I've tried Blueberries, Raspberries, Cranberries, Apricot(extract), Grapefruit (juice) . I have not tried elderberries, but that sounds interesting.
4 lb Red wheat, 4lb pale ale, 1lb Vienna, 1 lb flaked oats. About 20 IBUs of noble hops. For the original 'Orange Moon' I add orange zest and coriander seeds. For the blueberry and raspberry versions I add lemon zest and juice. The grapefruit version uses grapefruit zest and I dryhopped with Centennial. US-05 yeast. If needed I do backsweeten with a little Xylose at bottling.