Historically Dry Cleaners, and Toilet Paper makers have not been affected by economic depressions.
If your talking more a total collapse though, I think any job skill that was marketable in the middle ages, will once again become marketable.
Anyone that can produce fuel (soalar, wind, hydro) or fuel (bio-diesel) will be in HIGH demand.
Doctors, nurses, vetrinarians, denstist, and such will be in high demand.
Small farmers who can produce food for themselves, and some for market. Whether it's crops like wheat, corn, or carrots. Also the farmer who can produce animals which can be taken to market. The farmer who can produce smaller animals will do better...sheep, goats, rabbits, chickens, and such. Money will be worthless, and very few will have the means to barter for a whole cow. Besides a whole cow is too much meat if you don't have refrigeration.
Cobblers....know anyone who can make shoes from scratch? That's almost a dead skill.
Seamstress/taylor....clothes will start to go, mending needed, and new ones needed.
Laundry....this is actually a big one. A lot of people still line dry, but how about hand washing all our clothes? LOTS of work there!
Soap maker...many different kinds of soap needed.
Butcher, baker, and oh yes, the candle stick maker! Someone needs to know how to make bee's wax candles.
Carpenters, mechanics, and blacksmiths will all be in high demand.
Someone with REAL military training. You will need someone to patrol, and protect your community. (Policemen, and good hunters will work in a pinch, but nothting beats military training.
Gleaners.....gleaning crews may be needed if things are really ugly to try and scavenge/salvage whatever can be saved. (After all, who makes things like windows anymore?)
Ham radio operators....totally vital the survival of a small community.
Teachers....though teaching will change, and kids will be learning more about trades from a very young age.
Fishing, boat makers, lobster pot makers and such could be very important, depending on your area of the country.
Lumberjacks....new lumber is always needed.
Minors.....have to supply more coal, or iron ore.
Tanners....everyone will be wearing a lot more leather.
Teamsters....the original ones, ya know the men and women who could
drive a team of horses.
Saddle makers, also making bridle, harness, ect.
Wagon maker, and wheel maker (a hard skill to learn, I understand).
Tinkers...usually moved from place to place, and did small odd jobs, like mend cooking pots.
Traders.....I don't much care if okra comes west of the Mississippi, but I sure would like to see oranges again. Traders could bring in all sorts of goods.
Masons...putting up a brick or stone wall is quiet a skill.
Entertainers...jugglers, people who can do plays, and puppet shows, sing and dance, they will be very welcome in a reasonably stable community. (Not however in a starving one.)
These are just a few of the "jobs" I see as being useful, there are lots more I didn't cover, but I've got to go tend to my goats. I see one with her horns through the fence.
Crumbs from the cookie,