The highest-order compliment I give is to designate someone as Useful. This means that the person is a worthy candidate for my zombie squad. It's a simple shorthand for a complex set of attributes. It's entirely possible that I don't meet my own standard for Usefulness.
The first component of being Useful is to be a strategic thinker. The Useful person sees problems before they become problems. This is why the Useful person tends to know when to open doors or grab the other end of a heavy object. A full-on Useless person, on the other hand, tends to spend a lot of time in exactly the wrong place. Useless people cause accidents and spills, and stuff tends to get broken around them due to their inattentiveness.
My dog is both Useful and Useless, which is allowed because he's an animal. He is Useful in that he's vigilant, he eliminates vermin, and he always lets me know if a package has been delivered. I have watched him crush a spider with his paw, note that it was still moving, and crush it some more until the job was done. He also has a habit of trying to walk between my feet, especially when I'm carrying groceries or a laundry basket. He has knocked me over. He likes to dig up fresh seedlings from the garden. When he was a puppy, he destroyed nearly a dozen pillows. All of these things are pretty darn Useless. He likes to sleep on my feet in the winter, though, and that's so Useful that it balances the accounts.
A Useful person tends to have interesting skills that I don't have. I am a gleaner of skills, and I will try to absorb these abilities as quickly as I can. Often, though, I'm weak in an area and will have little hope of mastering it in this lifetime. Orienteering is one example. I have trouble telling left from right and I have no innate sense of direction. It's Useful to me to have someone around who is good at these things. I can offer a skill that seems like it would be closely related, but isn't: I have an eerily photographic recall of where objects are stored. I can remember the location of every object in my house and most of the visible objects in every house where I have spent significant time. I have helped people find their keys and other possessions over the phone from 3000 miles away. This is Useful for my work as a professional organizer - I can still recall the positions of visible objects from a Level 3 hoard. I can't navigate but I can find all the stuff, and my husband is the opposite.
A Useful person is solution-oriented. This means the focus is always going to be on solving a problem and moving forward. A Useless person prefers to vent about problems, cultivate allies who have an opinion about problems, and create drama about problems, while the problem continues to fester. The two groups tend to have mutual antipathy. Sometimes solving a problem looks a lot like "judging" anyone who didn't contribute to the solution. Why, I don't know. In my roster of Useful people are a few people who are abrasive, occasionally annoying, yet I can appreciate that they will reliably solve problems and get things done.
A Useful person lets the results speak for themselves. Useful people are often very surprising. You might know them for years and never know that they have a bunch of Useful traits. I was rocked back on my heels one day when I was walking with a friend and he ran into someone he knew from an old job. Suddenly they started signing to each other in ASL. Never thought to mention it, huh? Having a set of skills builds confidence. You can go through your day having interesting conversations or kicking back and relaxing. It may not occur to you to mention the skill to people. Maybe years will go by and you won't need to demonstrate the skill. Suddenly, bam, Useful!
Useful people are altruistic. This is part of why I fell in love with my husband. He took night classes and became an Emergency Medical Responder, just because. Since then he's been first on the scene at a couple of traffic accidents. I've been with him on a couple of occasions when someone collapsed, at the coffee shop and on the bus, and it's awe-inspiring to see that shift into superhero mode. We are fortunate enough to have several friends who have been Useful when someone else was in trouble. It makes you love them all the more for the way they unselfishly come to someone's aid, and also because they've just demonstrated that they deserve a spot on the zombie squad.
My most Useful moment was probably late one evening, when my friend's car had broken down in a small town where everything had already closed for the day. He was trying to replace the fuel filter, and the single tiny nut that held it in place fell into the gravel. We were parked at an abandoned gas station. There were about forty million bits of stray hardware in that gravel: springs, washers, screws, paperclips, bottle caps, bits of alien spacecraft, you name it. Somehow, with the sun going down, I FOUND that nut. My freakishly keen eyesight and ability to pick objects out of undifferentiated piles became my superpower that night.
Sometimes we're Useful without realizing it. I was waiting at a crosswalk one day with about a dozen other people. Almost everyone jaywalked. I always wait for the light, because I don't trust automobile drivers at all, and I would hate to be blamed for being pasted by a car. When I crossed the street, the last remaining pedestrian spoke to me. He was an elderly man and his eye was running with fluid. He told me that he was partially blind and that he counted on people like me to help him know when it was safe to cross the street. I hadn't even noticed him until then. I can't take credit for it; all I can do is to proceed with others in mind. Try to be the person that Future Self will need in times of frailty.
I hope I'm Useful at least some of the time. I don't want to be a "consumer." I don't want to be a complainer or a whiner. I don't want to get in the way. I don't want to annoy people unintentionally. (If I do it, hopefully it's on purpose!). At least I can try to be neutral, offsetting the irritation of my very existence by the occasional helpful act. At best, I'd like to be the one people count on when they think, "Who would I want with me during the apocalypse?"