Whether you're putting together a portfolio website or just slapping together some slides, knowing how colours affect the minds of your audience makes your message more appealing. Smashing magazine offers a post that serves as Colour Psychology 101 for would-be designers.
Beyond explaining which colours work as "warm" and "cool", how primaries play off secondary colours, and offering lots of keen examples of every kind of colour design, Smashing's post offers some clues on how colours are perceived when images are translated to mental impressions. Here's a little primer on orange that caught me unawares:
Orange is a very vibrant and energetic colour. In its muted forms, it can be associated with the earth and with autumn. Because of its association with the changing seasons, orange can represent change and movement in general.
Because orange is associated with the fruit of the same name, it can be associated with health and vitality. In designs, orange commands attention without being as overpowering as red. It's often considered more friendly and inviting, and less in-your-face.
Hit the link for a deeper read. While you've got your monocle and draft paper out, tell us what colour schemes you like, and which have never appealed to you, in the comments.
Color Theory for Designers, Part 1: The Meaning of Color [Smashing Magazine via The Red Ferret Journal]