I would the store the oil, although the small amount involved wont go that far, its still better than not having it!

As well as use as heating fuel, small amounts of waste oil are useful for lighting fires of coal or wood if kindling is not available, much safer than useing gasoline or kerosene, which would likely also be in short supply.

Also used motor oil is useful as a lubricant for low tech purposes, especialy if WD40 or "3 in one" oil are in short supply.

Another use is to apply it to saw blades, files and other tools to prevent rust, especialy on items not in regular use.

If I understand correctly, is is illegal to burn waste motor oil in a single family residence but it is legal in a multi-family, apartment or commercial building. Go figure.

There are commercially available waste motor oil furnaces, Kagi and Econoheat are names that come to mind.

It is possible to heavily modify a conventional #2 home heating oil burner to run waste oil, but it is a hobby in itself. Key ingredients include changing from a pressure nozzle to an air-atomizing siphon nozzle, preheating the oil and using a "turbine" style retention head to keep the flame short.

You can also burn waste vegetable oil in the same setup.

Lots of info can be found here:
http://groups.yahoo.com/group/altfuelfurnace
but you will need to do a lot of reading, no one there seems to be willing to lay it out in a FAQ.

Be aware that if you house burns down and the insurance company finds out that you tampered with the furnace, even if it is not the cause, you may have problems.

Since I have room to store it, I'll keep a stash. I don't think I'd burn it except in a genuine long-term emergency. I have other fuel sources at hand.

Oil is too useful as ... oil. I'm totally hard-core when it comes to reusing and recycling.

But I may do some experiments to learn how to use it effectively (clean burn etc.). This is a "resource" found all over, and if I'm travelling far from home, it could be useful.

Ultimately, I want to create a portable outdoor furnace for my acreage. Essentially, an insulated garden shed on skids that I can move from shop to house when I need it. Multi-fuel is the goal, and a combination of 12VDC and 120VAC fans to circulate heated air through insulated pipes. I just need time to put the parts together.

My understanding is that the anti-wear and anti-viscosity-breakdown additives are just as important as the base oil itself.

Time and heat break down these additives, which keep the oil working properly as a lubricant/coolant.

The reason my old Toyota Corolla got to 366,000 km and is still going is that I changed the oil regularly and without fail.

I wouldn't recycle oil in any vehicle I cared about, but in a long-term emergency cleaning/recycling would be better than doing nothing at all.

Just remembered another (totally off-topic) use for used motor oil:

Old-timer farmers used it on cattle to treat ringworm. Apparently it was quite effective.

Disclaimer: this is just a historical footnote, not a recommended treatment for people or pets. Anything that kills fungus is pretty toxic to everything else.

I've always wondered about these high efficiency oil filters that truckers use, like those from Gulf Coast Filters (just a random company I Googled). If you look on their page, they have various examples of rigs that have gone hundreds of thousands, even a million miles with no oil changes or just a single one, for the million mile rig. (Obviously, the filter needs to be changed regularly)

And according to the GCF website, additives mostly break down in response to dealing with the various contaminants that build up in an engine. They claim that since their filter keeps the oil very, very clean, the additives last a very long time because there is little contamination for the additives to interact with.

Yes, and they are sending lube oil samples off to the lab about every 1,000 hrs and then change the lube oil when the lab tells them to. They also change the regular and the special oil filters every 1,000 hours, when they take the oil samples.

That's interesting. It doesn't surprise me that a solution exists for heavy-duty industrial-scale applications. They will have done the math and decided if it pays off in the long term.

But that's a long way away from this tinkerer's garage with a ridiculous assortment of internal combustion engines. If I understand correctly, my used oil will already have broken-down additives because of the contaminants.

I sure wouldn't mind a super-duper filter system on my engines. It would save some work. Maybe we'll see that in passenger cars some day.