I know a business that wanted a website to match their brand, and it would seem that they are allergic to colour. I think designs in greyscale can look amazing, especially in print, but it feels near impossible to apply to website design.
In this case, the business was centered around social networking and new technology but a greyscale design I feel is rather outdated and didn't reflect at all what they did, even though, apparently that was their brand. (They said they were going for that 'Apple like minimalism style and sophistication' but perhaps they were thinking of Apple ten years ago) The business's website today is about as bland as cold white rice, (like one of those warranty documents you get with a new gadget you bought).
I recently received a request from a client who, for an architectural practice requested the same look and feel, without colour.
What do think makes a website look modern and interesting while lacking colour?