I love using Post-It Notes by 3M. I think these little sticky notes are the greatest idea. I use them for reminding myself of a lot of different things, and they really do come in handy.
I've even written short grocery lists on them and stuck the note to the inside of my handbag. They lift off easily without ruining what they have been attached to, and I really like the fact that they now come in different sizes and so many different colors. I use the basic yellow, and I also use blue, green, hot pink, etc. They stick very well to many surfaces, and these nifty little notes do a good job of keeping me more organized.
When I worked in an office, I used to come into work in the mornings and find Post-It notes stuck to my computer monitor from the night before when my boss was working late. They are so versatile and handy to have around. I've been known to carry a pack in my handbag in case I might need to write myself a note or to remind myself of something. It's amazing how these little notes can simplify your life.
I don't know if they are made from recycled material, so I had to put a zero down for this category.