I keep it pretty basic....use Photoshop (6 or 7 depending on which of the 4 computers I am on) - don't do much more than increase the saturation, alter the levels and contrast and unsharp mask...I do sometimes do a bit of burning and dodging if I need to work on a specific area of a shot. I do quite often crop a shot rather than process the whole image if I see something I like.
Every so often I go a bit silly and overdo things and got something like these....