Three years ago I spent many nights in a row sorting all of DS1's legos by color and putting them in bins labeled by color, but the system just didn't work out with how he builds. We have the big Nilo train table converted to a Lego table by adding the 4 Lego mats and extended legs and DS is constantly building things on his own and then having all the pieces scattered all over his table. It just takes way to long to go and clean up the extra Legos when you have to sort them into 11 different bins first! So now he has 3 large (43") floating Ikea Lack shelves on his wall to display Lego sets that he's built and wants to keep intact, then he has a bunch of built sets on his Lego table that he plays with daily and adds to, and then we have 2 large Container Store underbed storage boxes with wheels stacked up under his Lego table to store all the loose pieces. The underbed boxes work best because they are long and shallow, so it's easier to see pieces since it's not deep.
These are the under bed boxes we have:
http://www.containerstore.com/shop?p...bed+box+wheels
My best friend has a DS who is just 5 and is really into Legos right now. She keep all the pieces from each set he gets separate in it's own container with the directions so they can be rebuilt. Now this would never work for my DS who constantly builds sets and then takes them apart or adds to them with other random Lego pieces from other sets. Also, I could see how this would work if you have a younger child who has less than 10 Lego sets or something, but after 5 years of playing with Lego and getting 10+ new sets a year from birthdays and Christmas, this just wouldn't work in our household. This Christmas alone, DS1 got 6 new Lego sets from different family members.