One recently published algorithm is the Color Distribution algorithm:
D. Cheng, D.K. Prasad, and M.S. Brown,
"Illuminant Estimation for Color Constancy: Why spatial domain methods work and the role of the color distribution"
Journal of the Optical Society of America A 31(5):1049-1058 (2014)
DOI, PDF
In the paper there is also the reference to the Matlab source code (Internet Archive). It's a simple algorithm that can be easily programmed and the results show it to be very fast.
If you need additional fast and at the same time accurate white balancing (color constancy) algorithms, you should check this site.
There are several algorithms with their respective source coded that might be just the ones you look for.
