Like most humans I hate souvenirs that are designed to be souvenirs. Buuut I love shopping while I travel and I don't want to buy the same Zara skirt I can also get at home. (This list of general guidelines is inspired by @marisarico's great one abt specific things to bring back from specific countries.) Here are the best places to get cool things.
  1. The gift shop of the local modern art museum
    You'll find largely things that are just the international version of whatever they sell at MoMA, but usually there's a good selection of hip, artsy local products, especially in homewares and small gifts and the kids' section. I found a paper fox mobile in Madrid, some topographic-map-inspired ceramics in Portugal, weird naked-man-shaped soaps in Brazil, amazing rope bracelets in Bilbao, lacy die-cut playing cards in Paris. Also presumably you also go to the museum itself.
  2. McDonald's
    I'M SERIOUS. Get a happy meal. The toy is now your souvenir. This is how I landed a complete set of plastic Tom & Jerry kitchen accessories (citrus juicer! Popsicle mold!) on a trip to Porto. BONUS: you get a snack. EXTRA BONUS: McDonald's usually has great bathrooms. SUPER BONUS: also wi-fi. MAXIMUM BONUS: you can drink some Diet Coke out of a giant bucket like god intended
  3. The liquor store (bring yr cell phone)
    Go through the liquor store looking for any bottle you've never seen before. Look it up on your phone to make sure it's not available in the U.S. (Just google it + "price".) If it's not, buy it. Even if it's not that good (I once brought back some insultingly horrible Buddha-themed vodka from Sweden) it's so 👌 to tell your friends "oh yeah well it's not available here yet but everyone in [country you just got back from] is drinking it."
  4. The grocery store
    Same deal as the liquor store. Some plays are obvious: tinned seafood in Spain, chocolate in Switzerland. But especially pay attention to potato chips (weird flavors!), breakfast cereals, snack cakes and cookies (things meant for kids usually have the best packaging) and kitchenwares (sometimes you'll find brilliant products you didn't realize you totally needed, like a dog-shaped hard-boiled egg mold from Korea)
  5. The drug store (not just in Paris!)
    Women are brainwashed into being obsessed with French ~pharmacie~ products but there's treasure to be found in all countries' drugstores. I especially like looking for weird things like nail polish remover, aspirin, baby oil, and hair products. The packaging is generally awesome just by virtue of being different, and it makes great gifts.
  6. Used bookstores (or new ones too I guess)
    Buy anything that looks old, anything whose author name you recognize (buy more than one copy if you know the author personally, writers love getting more copies of their foreign editions!), anything with really neat cover design. If you super duper don't speak the language, your best bets are the cooking section, the art-book section, the kids' section, and the travel section. (I loooove buying other countries' guides to the U.S.)
  7. Your hotel's toiletries
    I was looking everywhere for really prettily packaged olive-oil soap while I was traveling through Jordan, and wound up realizing the bar of hand soap in my hotel near Petra was exactly what I wanted. I offered to pay for 20 bars but they gave them to me for free. And a lot of hotels in Paris — not just the fancy ones! — have Hermes toiletries; I came home from my last trip with basically a suitcase full or Orange Vert mini lotions
  8. The airport
    Use all your leftover non-US cash buying candy bars and weird-flavor potato chips and cans of whatever coca-cola variant they have wherever you are. Don't go to Duty Free, it's all just stuff you can get at home and saving six bucks on some mass-scale-produced cognac isn't really that exciting.
  9. If you travel a lot, start a collection
    I buy travel guides to America. My friend buys Harry Potter book 1 in the local language of wherever she goes, another friend always tracks down a rich-hipster home store and gets a scented candle. My mom always buys a scarf. If you come up with something to guide you, the process is simplified and de-stressed plus you develop a really cool collection at home.
  10. Hardware stores. Ingenious products from other countries. Especially in the kitchenware section. Good workmanship. Last forever.
    Suggested by @sharris