I finally went ahead and bought the cheap yet spectacular Nikon 50mm F/1.8.
I've had it a few days now and I have yet to take it off. There's something addictive about prime lenses like the 50mm or the 35mm (which I've used in the past but don't actually own) that's difficult to describe unless you've tried it.
I think it might be because it forces you to be more creative with your photos. With a zoom lens you can adapt the lens to the photo. With a prime, the only things that change are aperture and focus. It forces you to be more selective and creative with your framing.
It's very easy to take abstract style photos with a prime lens, especially one with a super-wide aperture rating.
The 50mm really is a must have for the frugal photographer.