Transbay Blog calls them the "Tenderloin Trio," three just-finished or upcoming projects geared toward low-income or chronically homeless families.
At the pace Tenderloin Neighborhood Development's going though, they won't be just a trio for long. The three: 125 Mason, its recently covered neighbor at 149 Mason, and a further off mixed-use project at Eddy and Taylor that should bring a much-needed grocer to the Tenderloin's liquor-store heaven (last we heard, Grocery Outlet was in talks, after British grocer Fresh & Easy took one look and bailed).
The plan is for 143 units, split between one-, two-, and three-bedrooms, plus bicycle parking. The chipper design you're looking at is courtesy architects David Baker + Partners, the guys responsible for the award-winning Curran House Apartments just a few yards down. Looks like the three musketeers will have to wait for the third though— ETA is 2012.