We can make a LOT OF EFFECTS. But, It won\'t be applicable on all medias like Print | Screen | Web.. with all Backgrounds. The standard design should be Clear on all backgrounds.
The best logo must be Good in
+Compatibility with Backgrounds ( Darker / Lighter)
I totally agre.It should contain small number of colors.It shouldnt be just text with some extraordinary font.
It need to be eye catching and interesting cuz those thing people easily remember.
And it should tell as much as possible about your firm.