Noise reduction software and the D70 is a perfect combination.
The D70's high ISO noise is very uniform and regularly spaced which is a breeze for software to remove effectively. Which also means one should not hesitate to use higher ISO sensitivities while shooting in lower light, without much fear of the consequence of noisy imge.
Eg: ISO1000 -
No filtering: http://dr-cbtan.fotopic.net/p5554529.html
Using Neat Image: http://dr-cbtan.fotopic.net/p5554528.html
In fact, the whole Langkawi Aquarium gallery here was shot at ISO1600 and cleaned up with Neat Image: http://dr-cbtan.fotopic.net/c160526.html