I have a hard time staying disciplined with keeping my parts in order so was looking for the easiest system to keep organized. I ended up going with the simple tackle boxes with adjustable dividers like these: https://www.amazon.com/Plano-23600-01-Stowaway-Adjustable-Dividers/dp/B011ZXH43Q/ref=pd_lpo_200_bs_t_2?_encoding=UTF8&refRID=K2KRB0W9HWVAGQAV9B69
or these: https://www.amazon.com/Plano-2-3700-Stowaway-Adjustable-Dividers/dp/B011ZXH9FE
Perhaps best of all they are only around $2.00-$6.00 (USD) depending on size and if you want a water tight lid (obviously not usually a necessity for this purpose). I started really just looking to organize Technic pins, axles, gears and connectors, but I quickly expanded to lift arms and now have pretty much my entire Technic collection under control. I have now just started working on our System Bricks last week and so far I think the approach works just as well. A big advantage of these boxes (particularly for Technic) is being able to know what you have in a given box at a glance. If I just need some spare Technic pins/connectors its one box, if I just need some lift arms, its another. Then the gears/axles/PF motors are in another box. And these boxes come in various depths and sizes and with static or movable dividers depending on how you want to organize each box.
The only downside is if I want quick access to parts that are spread among say 3-4 of the larger boxes at once, space for actually building can get a bit tight. I should add that i favor sorting by part type/size/bricklink category and not color. Also, my collection of spare parts is probably not as huge as many on here - I'll put it this way, each of my bricklink orders seems to be bigger than the last, and they are getting more frequent, but I'm not quite ready to sign up to be a seller ... yet. I don't know that this system would work as well for a big bricklink seller.