How far are you moving?
i successfully moved my 30 gallon freshwater tank and my 20 gallon saltwater tank and inhabitants on a two day car drive from virginia to texas. Im pretty proud of that, but it was probably mostly luck. what I did was like you said, last thing to be broken down. focusing on the marine tank for this post's purposes:
I put the LS and LR in a small tote with tank water. I got a tall kitchen trash can (nice thick one, brand new) with grooves in the bottom filled it halfway, and put one piece of small LR and the two fake silk plants I had (I had no corals or sessile inverts, I had to have something for decoration and hiding). Then I added the fish...1 maroon clown, 1 blue assessor, 1 scooter dragonet, 1 baby niger trigger, and all the crabs and snails. they got put in my backseat. I bought one of those outlet/cigarette adapters from home depot for like 50 bucks, double outlet, so I could plug in a submersible heater and an airstone. It was summer so I didnt have to worry about it getting too cold though. mostly had to worry about temp in the hotel room at night (try lugging in two trash cans full of water through the back door of the comfort inn without the employees asking you any questions). needless to say there was a floating thermometer in the portatank. I also had extra premixed saltwater and fresh water in case I needed to do an emergeny water change. I was armed with all my test kits and extra buckets etc. Oh i forgot to mention, since it was a long trip, I didnt feed the fish a full 24 hours before we left to prevent excess ammonia problems (fish waste). Then the poor things didnt get to eat until two days later, but three days without food isnt life threatening. so anyways, two days and a couple small water changes, oh and a half of a bottle of amquel later (supposedly removes nitrite and ammonia...)...drove into austin texas and the first thing to be unloaded? the fish tanks. a small cycle followed and everyone settled in just fine.
as far as corals and stuff I would probably go the bag-it-up route in the cooler like others have suggested. if its a short move it should be a cinch compared to my long trek halfway across america. two words: Drive Slow! Oh, and good luck!