We have been visiting Vienna the past few days and having great meals at some of the usual suspects like Walter Bauer and Weibels Wirsthaus, plus good gelato at Zanoni & Zanoni. Today was our first Chowhound find, at least something I haven't seen posted here. Just a couple blocks up Rotenturmstraße towards Schwedenplatz from Zanoni is a small, handmade organic ice cream stand called Heiling. They are doing some really great things. The fruit flavors seem particularly strong - the strawberry and lemon had great depth of flavor. The chocolate was also very good if not quite as amazing. The ice cream texture is top notch for all the flavors we tried.
There's lots of ice cream in Vienna of course, but this is really top notch, and with its convenient central location you don't even have to go searching for it. Ther's more information, including additional locations, at their website: http://heilingeis.at/.