B&W:
Tri-x for the classic b&w look, and versatility.. these days I use it with Rodinal & Diafine, depending on circumstances and intended look I'm after. Love it in both 35 & 120 formats. Bulk-rolled for 35mm to save cost.
Color Negatives:
1) Portra NC, absolutely love it to bits. Simply love the color tones from it, will really be sad once my stash runs out.. Really hate Kodak for discontinuing this great film!
2) Fuji 400H, gorgeous colors from this as well, balanced and natural, but still prefer Portra NC if compared side by side. Once my NC runs out, this will be my go-to film.
Color Slides:
Kodak E100VS, IMO it's almost like Kodachrome! & it's one of the cheapest color slides in town as well..