Deus Ex : New Vision is an overhaul of the environment textures in Deus Ex.
It's one thing to find such an extensive texture mod. It's another to find one that replaces the textures with so much care and attention that none of the high-res images seem out of place even on a decade-old engine! This is a huge revamp of Deus Ex that warrants an entire playthrough of the game just to see things in a different light.
DaveW put his heart and soul into this work and it shows. The texture work is exceptionally good and fits perfectly in the game; he clearly made sure that the custom new textures still capture the feel of the original very closely. Basically, there is really no reason anyone playing DX today should not use his textures, its that good.