Depends. For digital, it's:
Wacom Graphire small
Photoshop CS3 for everything.
For traditional:
Non-photo blue pencils for sketching
.05 mechanical pencil for linework and shading
Pigma pens in varying sizes
Grey tonal pens
White pens for highlights
Various paper (either sketchbook, bristol board, Comic ProBoards)
Prismacolor pencils
Colourless blenders
Markers
Acrylic paints
Various straight edges for, well, straight lines (rulers, T-square, triangles)
Flexible curve for curved lines
Mostly now, though, I colour my stuff in Photoshop, regardless if it was scanned or not.
Oh yes, and I utilize my library of art books for when I need references, poses, anatomy, proportion, and techniques.