So much for covering them with netting! A few days ago I gathered a number of goldenrod twigs with small galls, like the ones here. I put them in several containers with water, covered them with netting and put them by the window. Luckily the window stayed closed, because these three managed to escape (at least I am pretty sure that they didn't come from somewhere else but from the galls) and I found them. This photo was taken on 7/13/09 but I am not putting the date in the field.
They appear to be three different species of goldenrod gall fauna.
From one of these galls

Higher resolution image