During the day I'm usually using my Nikkor 28-105 f/3.5 from my old N90s on my D70s. I lose a little on the lower end because of the crop factor, but I also gain a bit on the telephoto end. This lens just seems to take better photos than the 18-70 kit lens that came with the D70s. Plus it has that nifty macro mode.
At night, I'm usually walking around with my Nikkor 50mm f/1.4 prime on.
I always have these two lenses with me, along with an old Sigma 100-300mm tele-zoom that does a passable job. I swap them pretty frequently during the day, depending on the circumstances.