The last shot is crucial. It's often what lives with the viewer the
longest and can certainly either confirm or change the viewer's
impression of all the went before; an impressive last shot can elevate a
mediocre piece of film making and a mediocre last shot can undermine a
film that may have had moments of excellence. See how many of these you
recognise and seek out the ones that grab you.
The blog this originates from looks like a great resource if you're interested in cinema greats or looking for some visual inspiration. It's called The Final Image.