we have a TON of legos in our house with all three kids loving them immensely! we actually have used the big 3-drawer rubbermaid type drawer sets that you can pick up at Wal-Mart or whatever... that's what we've used for the past few years. It provides a quick & easy put-away solution. I'm not so sure I works for organization AT ALL. it's basically a big dumping ground that makes it hard to sort through and find the pieces you want once the kits get intermingled.
we are actually in the middle of an all-kits rebuild project around here right now. we're rebuilding all of the kits we have, making notes of any and all missing pieces, and then we'll order them from lego, or maybe go to the lego store that's not too far from us. i think i'm going to devise some shelf display/storage system that will let us display completed assembled sets. that way they stay up and unharmed, but are easy to get to when they want to play with them. we'll see how this works.
i've also thought about getting the snapping storage containers that they sell in teh craft aisle for 12x12 scrapbooking supplies. they're big, but not super deep. i thought maybe storing each lego kit in its own separate container might be a possible solution. the pieces and the instructions could then go in together, and they could pull out legos one kit at a time. i've not actuallyl tried this yet though, so i don't know if it will actually work. sounds good in theory???