I thought I read somewhere about making cutting oil out of motor oil and kerosene ( seems dangerous to me but? )

I only buy synthetic 10w30 motor oil and usually only Mobile 1 but with the economy and the fact that my car has over 100000 miles on her, I have been buying whatever full synthetic is on sale , I usually have to buy 5 quarts and only use 3 1/2 ( Actually I use 4 because I use about a 1/2 to help flush the engine of the old stuff ) either way I end up with 1 quart of extra oil and I don't like mixing brands of oil in my car. Other than use it for lubricating gears in my machines is there a good use for it elsewhere in my workshop such as making cutting oil or something to that effect?

Might sound like a stupid question but I have a few quarts and am at a loss of how to put it to good use.