The district of Brigittenau is one of the 23 Viennese districts which really has not very much to offer at all. (The second one would be Rudolfsheim-Fünfhaus.) High percentage of lower class (many of them migrants), old and ugly blocks, no nice shopping streets at all and and no beautiful, wide plazas with monuments or other sights.
For most people, be they locals or tourists, there's only one reason ever to venture into Brigittenau, and that is the Millenium Tower, period. (This is just a skyscraper with shopping mall and cinema, erected at the shores of the danube so that we never will forget that we saw, and survived, the turn of the times in the year 2000.) Well, there's the Handelskai too, the quayside park and recreation area. Well, probably then the quay of the Donaukanal too. And apart from that - nothing, nada, niente.
But this is not quite true. The church on Brigittaplatz, for example, is quite nice, and sticks out here in Vienna as there aren't many red brick buildings in this town. It isn't an old church but a neogothic one, built in the 19th century; old, 'proper' churches here are made of stone.