I'd planned to put together a comprehensive article about the screenshot tricks, tools, and techniques that I use, and I'll get the chance to finish it up eventually. In the meantime though, here's a more-or-less complete list of the console commands that I use most often to set up and capture my shots - as a reference for myself if nothing else.

Console Commands - essentials

tfc 1
Freezes action and enables free movement of the camera. tfc without the "1" frees the camera but does not freeze action.

sucsm 1
sucsm allows you to set the speed at which  the camera moves... the lower the number the slower. Useful for getting the camera in just the right location since the default free camera speed is very high. 1 is very slow - I use it mainly for fine positioning in close to characters. 2 is roughly double that speed, 5 is still slower than the default but better for larger camera moves, etc.

tm
Hides all on-screen HUD and menu elements.

fov xx
Set the Field of View (FOV) of the shot, where xx is any number. Higher numbers are great for more wide-angle, panoramic shots but tend to distort objects near the edge of the screen or near the camera; low numbers are better for closeups but can show less on screen at once. 

Examples of use: I use FOV of 20-30 for most closeups where I want little or no distortion, play at FOV 75 most of the time, and often up it to 90 for wide-open outdoors areas. Low FOVs also allow for use of some cool cinematic camera tricks like forced perspective - more on that later. Tinkering with FOV can have a lot of interesting and unexpected effects on an otherwise mundane shot.

sgtm xx
Sets game timescale multiplier, where x=1 is standard Skyrim time, and lower numbers slow time down. Again, really useful for catching just the right point in a pose or combat sequence to freeze action and take a shot. This is different from the "set timescale to xx" command which sets the number of minutes that pass in-game for each minute of realtime - it's more like a bullet-time slo-mo effect that effects the speed of every actor and action on screen.

Example: sgtm .1 slows playback of most actions to 1/10th standard speed.

tgm
Toggle God Mode. There's nothing more annoying than getting killed while trying to take the perfect dragon-abuse screenshot. I'm shameless these days about toggling toggling God Mode on so I am immune to damage while I line up just the right heroic action pose.

tcl
Toggle clipping. Allows you to clip through scenery and to essentially "fly". Useful for positioning your character very close to another actor without pushing them away or to place your character on a roof or rock where you otherwise couldn't reach.

csb
Clears the screen blood decals from the camera, often useful when trying to capture a combat scene.

Console Commands - Advanced

tai
Toggles actor AI processing. Call up the console, click on an actor, and type "tai" to basically freeze them in place in the game - they'll stop mid-motion, even in mid-air, and won't react to any action you take until you toggle their AI processing back on the same way you turned it off. Very useful to pose an NPC or monster while you then go to position your character (or another NPC).

Entering this command when no actor is selected will, in theory, cancel all AI processing.

tcai
Toggles combat AI processing. Kind of like the above but less extreme. This just shuts down NPC or monster combat processing so they wont see you as an enemy. They'll still react to your presence, they just won't fight you.

If you click on an actor before typing the command, it only affects that actor. If you type it with no actor selected all active actors are affected.

tdetect
Toggles AI detection - again sort of like the above, but it renders you effectively invisible to AI actors. As usual if you click on an actor before typing the command, it only affects that actor. If you type it with no actor selected all active actors are affected.

tc and player.tc
Toggles controls. This is a bit of a weird one - if you click on an actor and type "tc" in the console you basically control that actors movements the way you would control your own character. By default you'll actually control both the actor and your character simultaneously unless you then type "player.tc" to relinquish control over the character. This is very useful to position an NPC in a position or pose, freeze them using tai, then move your character into position to take a screenshot.

disable and enable
Toggles engine rendering of an actor or object. Thinks you've got the perfect shot lined up but there's one annoying bandit who's blocking the camera? Click on them with the console up and type "disable" and they effectively disappear. Use "enable" to put them back into the game when you're done. Or not.

openactorcontainer 1
Opens an NPC's inventory the same way you can with a follower. Very useful to remove an NPCs helmet or shield, or to give them a different weapon in order to get just the shot that you need.

pushactoraway xx
Just what you think it'd do - it pushes the actor away with a force set by a number in place of the "xx". It's usually easier to use TC to move a character where you want them, but pushactoraway is a lot more fun since it acts on them physically - generates great ragdoll stumble/stagger effects as a side benefit.

I also use a number of useful pose and animation mods, but I'll save that list for the next article.

Let me know if I've left anything out, or if anything needs clarifying.