Photography camera lens help?

can you take a photograph without using a lens? i am using a nikon D80 and im trying out some experimental techniques, but im wary to break the camera as its not mine. I don't know a great deal about photography as i'm more into moving image, so can anyone tell me what will happen if i remove the lens and just take a picture or try and create my own lens. I'm trying to create mystical photos of water, i've been playing around with shutter speed and aperture, does any one know any other techniques?