Red is such an emotive colour - it means so much, to so many people, in so many cultures. Whether the first cave paintings or your political belief it means something to everyone. Always a joy to paint in as so powerful and positive.
For me unfortunately, red means the first company car I ever had - a bright red Ford Sierra - not something I was that proud of but it never broke down... (Something that every car I had ever had before and for quite a long time after had been seriously adept at doing... frequently.)