Whatever you decide to design, always make sure that when you invert the colors (ie make a black and white version of it for things such as Faxes etc), that the logo is still legible and still brings its message across.
The general rule of thumb regarding logo design is SIMPLICITY. You don't want to create something with lots of intricate detail.
Something else I remember from when I was studying design was that the lecturer also advised us against using gradients. The reason for this is because, lets say now you want to embroid the logo onto a t-shirt, there is no way that you would be able to get that gradient to come thru on the embroidery. I always keep this in mind - just in case