Some solutions are so easy and cheap that the question is why they aren’t adopted instantly. Two examples:
1. Refillable toothbrushes. The brand I use is Fuchs Ekotec and they’re readily available at natural foods stores and from many online natural products shops. You buy the toothbrush and an extra package of replacement heads, and just throw away the brush part. I love the convenience and just wish I could buy the replacement brushes 20 at a time.
2. Refillable razors. I have a nice wooden-handled shaver with a brass bracket (this one came from the Body Shop in the UK), and buy a pack of razor heads at my local drugstore (in the US) for it. Again, cheap, convenient, and good for the planet.
3. Concentrated laundry detergent. Why pay for water to be shipped all over the world? Concentrated liquid detergent is easier to get home and more conveninent (just be careful to use the correct measure instead of dumping in the same quantity).
Note: choosing the water-less or reduced-water version of anything is a great thing for the environment, because shipping water around the world has huge energy costs. Our drinking bottled water on the scale we do adds to global warming!