There are at least four key principles of visual design that have an important impact on usability. These four principles — contrast, repetition, alignment and proximity — were originally given the engaging acronym CRAP

Handy guide to A/B testing - the real value however is in the case studies at the bottom. If anything, they prove to me that there are no general rules you can apply to everything (i.e. green buttons). But that you have to test and see what works for you!

Interesting article - says people scroll but still give the section above "the fold" most attention.

Possibly the best way of handling forgotten password requests I've ever heard. I shall definitely be implementing this in the future