mason jars

I've done this. And I've modified it to fit my lifestyle.

If you're going to put in leafy vegetable greens (I recommend romaine lettuce and/or spinach), then you'll need a "wide mouth quart" sized mason jar. If you're going to do the kind without leafy vegies (where the base is something like lentil and/or quinoa and/or pasta) then you use the "wide mouth pint" size.

Edit to add: I ride my bike to work, so the "glass" jar thing doesn't work those days. So I also just use things like this for my "mason jar salads" http://galleryplus.ebayimg.com/ws/web/141002193191_1_0_1/1000x1000.jpg The leafy green vegies don't last as long, is all. But they'll still last 3-4 days, if you layer everything well and use a salad spinner to dry off the spinach.

wasting too much veg and salad

Also, consider a juicer (or at least a good blender). If my spinach or vegies go a bit wilty before I can eat them, they become juice.
Never waste good food! Mix some spinach going wilty into a yogurt and berry smoothie. Delish! Save the ends and peel from vegetables in a ziplock bag in the freezer. When you have a gallon-sized bag filled, make vegetable broth for soup/stews.

Those will pop open if you try to travel with them. For glass jar, you want something like this
http://www.uline.com/Product/Detail/S-17491/Jars-Jugs-and-Bottles/16-oz-Canning-Jars?pricode=WU333&gadtype=pla&id=72163105162&gclid=CNvHrKj1o70CFclDMgodTVcA8g

Edit:
Not that one, it's not "wide mouth". This one
http://www.uline.com/Product/Detail/S-19402/Jars-Jugs-and-Bottles/16-oz-Wide-Mouth-Canning-Jars?pricode=WU333&gadtype=pla&id=72163105282&gclid=CNiImMn1o70CFa07MgodDksA5g

or this one
http://www.uline.com/Product/Detail/S-19403/Jars-Jugs-and-Bottles/32-oz-Wide-Mouth-Canning-Jars?pricode=WU333&gadtype=pla&id=72163105282&gclid=CNz-xNr1o70CFQ5gMgodvx8AVQ

(Hell, I just used clean spagetti sauce jars to start with)

Nothing productive to add ...