Is teleportation or far step considered physically passing through the wall? Does it behave as an obstruction for spells like charm person, fireball, etc. where you just need line of sight?

Is teleportation or far step considered physically passing through the wall?

No, you do not physically pass through the wall when teleporting, which allows all teleportation spells to bypass the wall.

Does it behave as an obstruction for spells like charm person, fireball, etc.

No, although a Fireball created with a point of origin outside the wall would not pass through it.

If you are looking for a teleportation barrier, consider Forbiddance, Private Sanctum, Anti-magic Field or Hallow.

Any links to consequences of damage when colliding with WoF at speed?  Seems like a great deterrent for Sea Ships in Pursuit that you don't mind crippling.

Do it like falling damage and just add a few dice if it doesn’t seem to be enough.

I'm just imagining the effects of casting this ten feet above you as a large flying monster decides to dive bomb you... moving at high speeds right into this wall could be terrible. Also, traps. With this and a solid illusion spell, you could trick entire swarms of mobs off a ledge, or down a chasm... Imagine if you would, using a Wall of Force to cross a relatively wide chasm, then using illusion magic to make it look like there is a bridge crossing said chasm where the wall is, purposely lose concentration while the horde of whatever is half way across the chasm, lots of falling ensues.

D&D 5e designer Jeremy Crawford, whose rulings are considered official, confirms in a tweet that wall of force provides total cover: Q: could a wizard make a sphere around a creature using wall of force and then chill touch to damage them through the wall? Crawford: Unless a spell says otherwise, you can't target someone behind total cover (PH, 204) Also here, in specific reference to wall of force: Q: Wall of Force is invisible...so it doesn't provide cover does it? Crawford: Cover is a physical obstruction, not necessarily a visual one. The reason wall of force blocks spells is that it, as an obstacle, it provides total cover to anyone fully behind it as per PHB p.196: A target has total cover if it is completely concealed by an obstacle. Crawford's ruling confirms that "concealed" here is a synonym for "covered", not "invisible" as it meant in earlier editions of the game. And, as per PHB p.204, this prevents a caster from targeting you: To target something, you must have a clear path to it, so it can't be behind total cover.

It would be incredibly resource intensive. Wall of Force isnt a concentration spell. When you cast it, it's there for better or worse unless you disintegrate it.

So yes, it's possible to use it as a bridge, have illusoil over the bridge (major image or better) and then run across it, then disintegrate the wall while minions are on it. But you've now used  a 3rd, 5th and 6th level spell slot.

But it's a concentration spell, it's duration is <c> 10 minutes. So you can drop it anytime you wish.

As Frankish said, it is a concentration spell. Not to mention three spell slots is an absolutely reasonable price to pay depending on the situation, not that they would need 3 spells, since they could just break concentration. Other fun options would include things like force walling a bunch of enemies into an enclosed area with an already in effect AoE spell or ability. In these cases, you would need multiple casters to manage this easily. Ultimately, there are plenty of options and uses to this spell for fun and creative effects. Hell, just pop this wall directly in front of a cavalry unit at full pace.

Wall of force is just a pretty interesting spell all around, and I am sure I can come up with more interesting ideas.

"The wall also extends into the Ethereal Plane, blocking ethereal travel through the wall."

Would this also prevent Banishment if the target is inside a wall of force?

If this is used in sphere form around an open and upside down endless decanter of water, would it continue to pour even after being filled with water until the spell ends?

If so, if someone manages to make a permanent wall of force in this situation, would the amount produced eventually gain its own gravitational pull that exceeds that of the planet, up until it makes a black hole upon disintegrating the wall of force? 

The spell says that nothing can physically pass through the wall. Does this mean that when you cast it, it the entire area of the wall would need to be clear of walls/ground/etc? It's not as large an issue with the flat implementation as you can limit the size, but with the dome/sphere it could be difficult to properly place it.

Lol. I was going to do this in a campaign on my last session I was even going to lie it under the surface of the water horizontally.  Unfortunately, they didn't get close enough to try. I had to settle for blocking the whole side of the ship rendering it invincible to their canon fire. (Sigh) lol. I also used it to severe the tentacle grapple of a kraken on my entire party in one move.

The decanter requires a command word every round to continue pouring in 5e, so that isn't going to be an issue.

i'd say it only occupies any unocupied spaces, but that also leaves the problem of people digging under my fabulous dome of force, so maye create it in the sky?

Can I cast a Sickening Radiance into a Wall of Force (presumably cast by another caster)? Can I just Chill Touch people inside a Wall of Force for 10 minutes?

We literally just had this happen in my campaign. A player managed to cast it as a Wyvern was strafing. It was pretty smart and effective.

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Quote from MidniteOil21 >>

"The wall also extends into the Ethereal Plane, blocking ethereal travel through the wall."

Would this also prevent Banishment if the target is inside a wall of force?

It only blocks banishment if the caster is on the opposite side. Not because of the ethereal plane, but because the wall of force gives total cover. 

And, as per PHB p.204, this prevents a caster from targeting you: To target something, you must have a clear path to it, so it can't be behind total cover.