KissMetrics have published some really cool research on how colour affects consumers purchase behaviour, below are two extracts but you can see the full size info-graohic on the KissMetrics blog.

According to the below, visual appearance overall and colour in particular are major factors for consumers when making purchase decisions and given the easy of which we can change both in an online environment this would lend itself to some great tests.

Colour psychology has been around for a while but the below opens up a whole new world of real-time online targeting based on colour response patterns. There would obviously be some serious limitations and difference between brands but what if we could segment anonymous visitors based on their colour affinity and then show them different offers and messages? Worthwhile investigating I think.