I use Kodak Portra 160 (NC or VC, depends on the subject) negative film (35mm). This film gives very natural looking colors and a good representation of skin tones.
I would like to use Fuji Velvia for some landscaping photography because of it's dramatic color saturation. Until now the higher cost for professional quality prints from slides has kept me from using slide film. I might buy a new scanner and digitize the slides myself.