Cut-back Shrubs:  Article from Nan Ondra on Cut-Back Shrubs (coppicing)

When pruning a cut back shrub like Cotinus smokebush, or Lupulus golden hops vine, root prune it as well in early spring.  Otherwise, the roots get very large and store enough energy to fuel too much growth as it leafs out and it gets too big even in one season.

For denser regrowth, cut the newest stems as they regrow -- in late May cut the new growth of the smokebush back a second time when it has leafed out to about three or four feet high.  Cut back each new stem by a third then.
               First, coppice to 2 foot frame                                    Then when this size, cut back new stems by 1/3

Note that when cutting back, cut willows all the way to the ground, don't leave even a few inches.

Boxwoods:  Article on Pruning Boxwood

Forcing:  Article on Forcing Branches in winter
After bringing the branches inside, fill a sink with very warm water—as hot as you can stand it. Very warm water contains the least amount of oxygen. If oxygen gets into the stems it can block water from being taken up, preventing hydration. Hold the stems underwater and recut them at a severe angle an inch or two above the original cut. The stems will quickly absorb the water.

Hydrangeas:  How to prune and other info in general

Montauk Daisies:  How to keep from flopping.

Clematis:  How to prune (3 groups)

Here's an even easier way to figure out pruning of clematis, especially if you don't know what group it belongs to. This is from Nancy DuBrule at Natureworks:

"If the flowers come out in May and June and then there are no more flowers, it blooms on last year's wood. The time to prune it is right after blooming, in late June and early July, and then leave it alone for the rest of the growing season. (Niobe)

If it doesn't flower at all in the spring but starts to flower in July and continues for the summer and into the fall, it blooms on current year's wood. You then have my permission to cut it to the ground every spring and enjoy a fresh, new plant each year. (Jackmanii and Alba Luxurians, although I cut Alba L. to the ground in August and get regrowth and rebloom in Sept.)

If your clematis blooms in May and June, takes a rest from flowering, and blooms again late summer or fall, it blooms on both last year's and this year's wood. You have a couple of options. If you are like many people who don't understand clematis and have consequently left your vine alone for years in fear of damaging it, you have a giant tangled mess on your hands. In that case, cut it down in the early spring, sacrifice the early bloom season, and get control back of the plant. You will still enjoy the late season flowers. If it looks pretty good and you don't feel like it will tear down the trellis anytime soon, do a light pruning in the spring and a second light pruning in late June or early July after the first heavy bloom period finishes."
            ---- quoted from her blog post March 11, 2013

For the tricky Group B -- a note:

Prune back to a height of roughly 18"-24" the first year regardless of its pruning code!!
This will encourage branching and multiple stems from the buds underground. This is particularly important for group B clematis (Henryi) which are notoriously reluctant to fatten up at the base. Two or more years of this treatment may be necessary for the plant to develop a satisfactory framework, but the rewards in terms of future flowering and general appearance are well worth it. (During this time flowering is not sacrificed, rather delayed until later in the season.)

Conifers:  How to prune all kinds of conifers

White pine saplings: wait till 3rd or 4th year for first shearing, or when leader is 10 inches. Then cut the leader back to 10 inches (at 45 degree angle).  Cut the top lateral branches about 4 inches shorter than the leader, and cut lower side branches to taper.  Cut only new growth.

How to prune pines video (while growing)

How to prune spruces video (while dormant)

Suckering Shrubs:
There's a good example (picture) in this post on cutting suckers off a suckering shrub like a witch hazel. Shows what the branches look like that should be taken off down to the ground.
How to remove suckers on a witch hazel

How to top cut for shape, remove older canes, and look for problem branches.