Cold Weather Additives

by Chris

Is there a way to make biodiesel less viscous. I am planning to use waste cooking oil to produce the methyl esters. I realise that I will need to assess the cloud point of the fuel with each batch.
In regards to cold starting in colder climates I hear that in Siberia they add gasoline to diesel to lower the cloud point of the fuel. Would that be possible assuming I use a viscometer to determine what mix leads to the same viscosity as regular diesel or is there a more economic route to reducing the viscosity and cloud point?
Thank you for your help.
Chris