Emil's right, good light makes decent photography ten times easier. I find that lots of pictures taken at dusk look great through a viewfinder but dark and useless on a screen/paper. There only so much you can do in post with a too dark photo.
My other favourite trick at the moment is shooting with the largest aperture possible (hence fastest shutter) to give a small depth of field. Great for portraits (people and cars!) as only your subject is in focus so you get less distraction.