Patagonia ran this ad on Black Friday. Sales shot up 13 percent over the previous year.

Nothing like deprivation to muddy up your understanding of “want” vs. “need.”

For instance, here’s a sampling of items I’ve considered “needs” over the past two weeks: new sports bras, shower curtain, new couch pillows, lime-squeezer kitchen gadget, iPad case, duchess satin bridesmaid dress, cat scratching post, and a handmade silver ring shaped like a poppy. This is doubly remarkable, as I’m not really the shopping type. But I’m also in the middle of a self-imposed No New Stuff May, and we all know what happens when you start branding the fruit forbidden.

My No New Stuff month is a challenge not to buy anything brand-new for the 31 days of May (food and certain toiletries obviously excepted, you sickos). Why? I already have everything I need to stay hale and hearty, and my small apartment wouldn’t fit much more stuff, anyway. But really, it’s a small stand against a “Bigger, Better, More!” culture that tosses perfectly good items into landfills and gobbles up new resources to build still more stuff — much of which we don’t even need.

That’s not to say I’m going native, eschewing capitalism, and weaving a new wardrobe out of grass clippings. Under my challenge, buying used stuff from resale shops or Craigslist is street legal, as is repairing broken items and just plain doing without. I began without any pressing needs on the shopping front, curious to discover what desires might pop up as the month went on and how well I’d be able to satisfy them. And just as I used to hide forbidden copies of Sweet Valley High books under my bed as a kid, now that new purchases are taboo I’ve been deluged with strange wants masquerading as needs.

Take that iPad case. First off, I didn’t even buy the iPad itself — I wouldn’t have one if an employer hadn’t sent it to me for work on a media project. Its original box has provided perfectly adequate shelter for months. But now, all of a sudden, I’m gripped by the need (er, want) to tuck the iPad into a stylish, hand-sewn case. “I have the thing — shouldn’t I protect it?” I argued with myself. “Won’t that make the iPad last longer, and isn’t it therefore the greenest choice?”

I haven’t yet caved to the gadget lust, I’m happy to report — and wonder of wonders, my life is still fulfilling. Same deal with the lime-juice squeezer. (I’ve been using brute hand strength to squeeze limes since my first batch of guacamole, and dammit, on brute hand strength I shall continue to rely.) And the poppy ring and the couch pillows? I’m just fine without ‘em.

Then there are the lazymakers: worn-out items that are easy enough to refurbish, but even easier to toss and replace with new models. Who among us hasn’t been at least tempted to dump a long-in-the-tooth item in favor of a shiny new one? Or worse, throw away a still-serviceable item just because we feel like something new? Maybe nothing lasts forever, but I can’t think that way this month. This month, I’m duty-bound to attempt resurrection.

Luna likes her refurbished scratching post just fine.

My first project was my cat’s shredded, two-year-old scratching post. Luckily, cats don’t care about having the latest thing in claw-sharpening technology, so she didn’t object to my taking a tube of Krazy Glue to it the other morning. The post — which I originally bought used at Goodwill, by the way — is just an old traffic cone wound with sisal rope. After 10 minutes of carefully reattaching the fibers to the plastic cone, voila! Good as new. Mint-condition scratching posts at my local pet shop start at $30, but this re-upholstery session cost me a cool $2.79 for the tube of glue (new, not used, I confess).

On a roll, I decided to freshen up our old shower curtain. It had put in a couple of years of solid service, and was basically fine, if rather grimy. Before No New Stuff month, my admittedly spotty thinking on the matter had been, “Shower curtains have a limited shelf life, right? At a certain point, they just get too gross to save.” Maybe, but honestly, mine was nowhere near that point. So I sighed, yanked it down, and spread it flat for a deep cleaning.

Eeew. Apparently, I’d missed a few deep crevices during my last bathroom-scrubbing frenzy. Several remote canyons among the folds were in open revolt, having been colonized by streaks of black mildew when I wasn’t looking. I took a deep breath, soaked a sponge in vinegar (so acidic, it’s like taking chemical weapons to household bugs), and went to work. To my great surprise, the grossness wiped right off. And to think, I was ready to throw the thing away.

With two weeks still go to, there are still plenty of desires left to battle, and plenty of resale shops and online swaps left to comb for the items I just can’t do without. I’ll report back on my trials and triumphs next time. Meantime, thanks to my No New Stuff challenge, I now know what Lazarus felt like — or my shower curtain does, anyway.

How about you — have you ever imposed a No New Stuff challenge? What was toughest? What tricks did you pick up along the way?