Before:
http://i36.tinypic.com/2b5s8n.jpg
SAW (50 cal?) army ammo can, weatherproof solar panel, etc

After:
http://i37.tinypic.com/2mnexqo.jpg
Suggestion: If you ever decide to spray paint one of these army ammo cans, you should grind/sand off all the powder coating looking paint first. With all the surface area I thought it would be a good surface for spray paint. Its really not that great, the spray paint kept peeling off with the masking tape and I had to strip it back off in places a few times. DONT USE MASKING TAPE, USE PAINTERS TAPE!

Grip on the bottom:
http://i37.tinypic.com/23ualc8.jpg
This was a bitch. I sprayed a couple layers of that spray on rubber tool grip onto the bottom. Then I found some fabric, cut it out and put it on top, ran a bead of some shoe goo type rubber cement to keep it in place, then sprayed over it all several times. Works ok. If I did it again I think I might just go find a place that sprays on truck liners.

Inside:
http://i34.tinypic.com/2zyx547.jpg
12v 33Ah deep cycle AGM battery. If you decide to try something similar, check craigslist for a few weeks, don't buy it new. I missed a chance to get 4 of these type batteries lightly used on craigslist for the price of 1 of them from a battery store new. There is a wood insert on the bottom to stop the battery from sliding around. Wiring is ugly right now. The meter is a "Watts up" meter. Checks voltage, amperage, watts, amp-hours, watt-hours, min voltage, probably max voltage, etc. It cycles through stuff automatically and IIRC is good for 50A continuously. It has a very low power drain and pretty much just acts as a wire. I have it set up with a small switch to its left so that I can reset its amp-hour/watt-hour counters at any time without disturbing the power to any load currently on the battery. If you go online to buy one, theres a store on ebay that is cheaper than the main distributer, thats where I got mine. Didn't come with anderson power poles so I added my own. The solar charge controller doesn't appear to work so I'm kinda pissed off at that. The panel my just be too small, or the panel could have gotten fucked somehow. Future testing will tell.

Anderson Power Poles (35A):
http://i33.tinypic.com/rko5yu.jpg
Kinda pricy, but love these things.

Free space for inverter, variable dc-dc converter, switches, tools, etc:
http://i34.tinypic.com/5f1c06.jpg
http://i38.tinypic.com/xlf894.jpg
Theres a nice slimline inverter I've been looking at that might fit in that side area. Not sure if it would have enough ventilation though. Theres a bitchin dc-dc converter I'd love to get but is currently quite pricy: http://www.all-battery.com/tenergyuniversaldc-dcconverter--anyvoltagecontrolnew.aspx
And apparently the company that designed it originally is working on a better one with a higher amp rating. Don't know if it will come out anytime soon though.

Float charger, power poles to other connectors adapters, external outlit cover for future modifications, binding posts, distribution block, covered switch, etc:
http://i35.tinypic.com/242zrqv.jpg
Thinking of making an altoids size box that is connected to the main battery, but on a 5ft or so cord and putting the binding posts and some other style connectors in it so that most normal dc connectors can be hooked up to the battery.

In-line water resistant fuses:
http://i36.tinypic.com/2roooig.jpg
Just in case. I'd carry several different rated spares too.

Purpose:
To provide 12v DC and in the future 120v AC (possibly along with a variable DC-DC converter making charging cell phones and such more practical) for small non-power hungry applications when power isn't available otherwise, OR when it is available but you would rather not take the risk. IE using your car battery when its crappy and your in the middle of no where and if you drain it too much it wont start your car up and theres no one to jump start you around... My car sucks. I'm mostly going to use this as a power source I can keep in my car and run my ham radio off as needed. In addition it will be nice for camping powering LED lights and such.

Future similar projects:
I have 2 smaller ammo cans. I'm thinking I'll turn one into a first aid kit for my car, and the other into a survival kit with fire starting materials, mess kit, compass, fishing line, etc etc.

Summary:
Do not trust masking tape for masking when painting, use proper painters tape.

Thoughts? Comments?

most of it looks good.

but I wonder if you have acknowledged the different needs for lithium-ion , versus lead acid and ni-cad batteries.

Hence the voltage / amp-hour meter to make sure the depth of discharge doesn't go too far yes. I intend to add a little laminated table with voltage/depth of discharge and other nice info eventually. It would be nice to have a hard switch to shut it off if its discharged to a certain point, but it could be a hassle if it was a real emergency and you needed all the power you could get. In addition it would be more shit to buy :/...

I had looked into lithium polymer, lithium ion, nimh, ni-cad, NiFe, and SLA... SLA is easiest to charge via solar, wind, treadmill, etc, you don't see many products out there for charging li-poly, li-ion, nimh, or ni-cad via these as it can be tricky and may need specialized circuitry. In addition they are all still really expensive. For SLA I don't even really need a solar charge controller per-se, just a blocking diode and solar panel. Ni-Fe would have been nice if I could find them OTC. They self-discharge faster and don't charge as efficiently as SLA... BUT you can use them until they are dead and charge them up again without damaging them at all. Basicly 60+ year life span when abusing them in exactly the way SLA shouldn't be used and minimal maintenance... Some day I'll get some... there are still a few sources. Really pricey though.