On the opposite side of Archer street to Bocca di Luppo is Gelupo, the restaurant's fledgling gelato outlet. When I dropped in this evening, it was only two hours old!
They had a range of gelati and granita classics, plus some interesting flavours like pine nut and fennel (good!), or ricotta and coffee. Gelato was smooth and flavoursome, and definitely worth a look.
They also appeared to have a few Italian groceries at the back of the store and some other non-gelato food, so perhaps others could report back on more of their offerings!