(http://i.imgur.com/zNjZml1.jpg)
I don't think there is one at the moment. Prior to the renovation of the old court house / sky bridge to connect it to the new court house it was a surface lot. I'd imagine it'll probably turn back into that soon.
It's where Amazon is putting its headquarters when they relocate to Jacksonville
I don't believe there's anything going on with it but it is definitely an example of a prime property COJ/DIA should issue an RFP for development. Given the popularity of mixed-use multifamily infill development, this site would be perfect for such a use.
I believe at some point there was a 12 story tower proposed for law offices
^That lot is the one behind the Ambassador Hotel. It's two blocks north.