I use a spray mister called a FogBuster (http://www.fogbuster.com/) Coolant Sprayers: Fog Buster is a non fogging coolant sprayer mist systems, machining sprayers, spray lubrication system, metal rolling and forming lubrication system, oil mist cooling, metal coolant nozzles, spray lubricating systems, cnc machine made by a company here in San Clemente, CA.
I have been using them for 8 or 9 years now, and so far they have worked perfectly.
They use a pressurized tank and a reduced line pressure to push coolant out.
I run a line to the sprayer with 100psi and then regulate the spray down to between 6 and 12psi depending on what I'm doing, and I have absolutely no mist floating aroung in the air.
If you look at the other sprayers that use refined vegetable oil, also look at the cost of the liquid. That can run as much as $75.00 per gallon, while the FogBuster uses CoolMist products or any non parafin based liquid.
Remember though, a spray mister works really great on surfaces and side cutting, but I have found that it doesn't work that great for operations like drilling, tapping and pocketing.