Lets hear some plans, any spell in the books, any power of a conjurable spirit, and powers of reasonably tame paracritters (or that do not require the paracritter be tame).

A simple start: Shape Earth to cut out on about half the mining equipment neccessary.

Old standby: Movement on vehicles

now that that's out of the way:

Levitate: loading cranes go bye-bye.
Shatter/Demolish: wrecking cranes are gone.
Why buy poison when you can Slaughter Devil Rats?
Any Shape spell
Sterilize: keep doctors and surgeons happy

Here's a simple concept: Object Resistance for the Win. See a spell can only affect something if it gets hits sufficient to hit the object resistance. Natural substances, such as dirt, bacteria, moss, etc. have low object resistances, while processed items have high object resistances. That makes using manipulation spells on valuable stuff like computers really hard. But using spells at very low force to remove unprocessed materials from processed ones works just fine. Straight up Power Ball, when used at Force 2 or 3 will destroy everything in a shockingly large area that isn't a microchip. Which is amazingly valuable when you are in fact synthesizing microchips.

-Frank

DP.

Powerball for large scale demolition.
Fix for repairs of expensive devices

I think one should factor in the cost/gain ratio...

Mages are rarer than loading crane drivers (or computers doing the same), so applications would be restricted to stuff too expensive otherwise

You must have not played in the same games I have.... Everybody's a mage or an adept. Funny how that works out.

The main limitation is that the max mass is going to be only a few tons, even with SR character density of mages.

make a spirit power some kind of treadmill or a water-spirit power a water-mill, or an air spirit power a windmill, or an fire-spirit powering a power-plant that burns things . . use one fixed spell of light to power solar-cells and other photovoltaic stuffies . . obvious use of wealth-power comes to mind also . . earth-spirits who work in the digging industry, coal-mines and the such . . they probably don't even need to DIG . . they just use shape earth to filter out anything valuable and leave the soil right there where it is . . maybe on the upper crust in the same moment ready the soil to be used as a field to grow things on . . task/worker-spirits can do almost anything . . water-spirits using shape water spell to help fisherman catch the fish by caging the swarms in an under-water cage where the net only has to go through . .

The Main PROBLEM is, that such things would probably cost hundreds of thousands of people their jobs in the end . . and it would fuck up the economic balance by generating more supply then there is demand for . .

The stock market will love it.

You know, that's Just Not True. The United Arab Emirates has one of the fastest growing construction businesses on Earth. People are coming into the country from all over the world to work construction, and they still don't have 30,000 loading crane drivers - not by a long shot. But they will have 30,000 magicians on population alone before they import a single person.

Now as it happens I do not think that loading cranes will be completely replaced by magicians. Most magicians don't know any particular spell you happen to think of, so tasks that need to be done a lot of times probably won't get parted out to magicians as a matter of course. The machine is reliable, reusable, and always available. Drain is also a factor: John Henry beat the steam drill, but he died doing it so the steam drill was still the more economical choice. Levitation is more accurate than cranes and can take materials as high as you want to take them (out to line of sight, holy crap!). But it really only does a couple of hundred kilograms at a time on the outside. So you'll see magicians brought in to help put delicate stuff on top of big buildings, but you won't see magicians raising the central girders of sky scrapers. It's outside of their mass restrictions, and there are too many for them to raise with the amount of castings that they actually have before everyone with the spell passes out from drain.

For these reasons and others, you'd more than likely see magic used only where it acts in a complimentary fashion to technology (such a Movement, Fix, and Heal), or where it acts in a way that technology can't (such as Glue, Guard, Shape Metal, and Power Ball). Places where magic is simply another way to accomplish the same goal as technology would in almost all cases go to technology. Because when your corporation is in the planning stages the technology is a known factor and finding a magician with the right spells is not.

-Frank

What about a Nuclear Spirt (Not all of these have to be toxic-right Frank) running the power plant of a reactor? The mage does not have to be a Toxic Threat, how about a Hermetic Engineering Magical Whiz in Nuclear Physics?

These two examples won't work very well. Levitate has a weight cap based on successes, and can't lift anything so heavy that a pair of burly trolls can't lift it easier. Alright, so you can lift it 200 feet in the air, but you won't have the dexterity to secure it properly. So that is pretty limited. Shatter has a huge drain code, which means you can blow a wall, maybe two, before you're out for the rest of the day, whereas a wrecking crane can go all day (and now, with better sensors and so on, probably all night too).

A mage is useful in the construction industry in that he's sort of like a swiss army knife. Drain means he can't do any particular activity well or for especially long, but he can do a LOT of activities without any specialized equipment. Need a trench? Don't bother getting a trencher, your mage can do it. Need a single wall out? Same. Need the copper extracted? He could write up a spell for that. Need to tie together two wires which you can see down a ten foot hole? Mage fingers. But in any case where you're doing the same activity on a large scale or over and over, you'll want the actual equipment.

Magic allows people to do a lot of things which are very difficult to do now. Catalog, sterilize, and otherwise determining patterns, gathering data, and doing very fine work over a large area are all trivially easy for a mage, but time consuming for anyone else. As has been pointed out, object resistance means a mage can instantly sort between processed and unprocessed goods. The fact that spells can be attuned to a particular object or substance means things like extracting minerals from recycled computers, currently a hugely expensive process, becomes easy.

Astral perception/detect truth/whatever is great for any sort of job which requires interview skills, such as hiring on new personnel.

If you allow 'create foo' or whatever, then it really is hugely powerful. If you can create food or create water, you can also create compressed hydrogen or unrefined gold. Imagine for a moment if you had a mage who once a day could create half a pound of gold. Current prices, that's about $8,000 in a single day. There's a reason why I ban all 'create' spells in my games.

Well, in SR 4, there isn't any 'Create Food'-spell anymore, only the sustain-spell-thingie, so in that regard, the game developers seem to have learned from it... At least...

Summoners and Conjurers will be worth their weight in diamonds. They create magical robots (who can teleport themselves wherever they've been before!!!) with the ability to grant the Speed Force (Every Spirit), make so that people won't ever have an accident (also every Spirit), or can search valuable ressources in seconds (Plant and Earth Spirits), or can even control the WEATHER (Water Spirits) !!! They can replace anybody (Task Spirits)!!!

Spellcasting is 2nd rate in industrially applied magic. Summoning materialisation spirits is where the future lies in Shadowrun, and where the official Shadowrun World will see tons of them working in places where once humans used to do the work, but now joined the masses of the unemployed SINless.