The next walk-around, inexpensive lens to acquire is none other than the recently introduced Nikkor 35mm F/1.8G. Highly recommended to shoot wider than her 50mm sibling, while not burning a hole in your pocket.
You can say its a lens every DX owner should get! In its use, you would almost, always shoot in Aperture priority mode, giving you and I tons of flexibility to dictate the desired DOF. At 35mm, it marginally make it to sensibly allow street photography with it, while equally applicable for some indoor people portraits.
A steal at $200. I have just placed an order for it, but who knows when it will actually come! It's just a shame Nikon don't do a 35mm F/1.4 like Canon.