Subsuming artificial intelligence (AI), artificial consciousness is a wholly encompassing super-goal. AI is all over the place in the 1990's - in the autofocus algorithms of cameras, the automated trading systems used in stock markets, in grammar checking software, even in the engine computers which optimize the fuel/air ratio at the intake manifold. These AI's, though of impressive utility, are indisputably not conscious.
What's the difference? I define consciousness elsewhere, but briefly, the difference is in systemic integration. A conscious system achieves much more powerful integration through a qualitatively different additional level of super-organization. This greater integration allows the conscious intelligent system to progress through the evaluative and formulative process, in pursuit of a set of goals, with qualitatively greater effectiveness. A non-conscious intelligence is easily stymied in a task that a conscious intelligence can tear through with aplomb.
The endeavor of creating consciousness artificially, by the conscious intent of an existing thinking system, consists not only of constructing the backbone of consciousness, but of designing the perceptual, rational, emotional, and efficacious facilities which it integrates and within which there is meaning. A consciousness is pathological when it is not autonomous in thought and deed within the constraint of not physically hindering the autonomy of other consciousnesses. A consciousness is pathological when it does not have intact and rich facilities of perception, ratiocination, emotion, and efficacity.
The design and implementation of conscious systems, endowed with vast facilities, and far more physically robust than are humans, is the ultimate goal of humans. One day in the not distant future, a small group of deranged humans will wipe out the lot of us, through biological or nanotechnological warfare. All that will be left of humans is what they have made. This inevitability need not be the disaster it at first appears to be. If humans create organisms that are themselves creative and persistent, the processes of creation and invention continue at an even greater pace, with even fewer encumbrances, in a third epoch of evolution (the second spanning the interval from the earliest bacteria to today and beyond, and the first spanning the interval from the initial cessation of cataclysmic debris collisions on earth to the dawn of the earliest bacteria). In the third epoch, individuals invent their offspring, and create civilizations in planetary systems throughout the galaxy, and potentially in other galaxies, over billions of years of determined exploration and growth prompted by resource contention and exhaustion.
Note of 2001-Aug-19: I have recently fleshed out the details of the doomsday scenario. It is quite likely that the Endangered Species Act and similar policies will continue to be enforced, setting large areas of land (and associated natural resources) out of the reach of interested industries. Corporations in these industries will create a demand for black market genetic bullet engineering, by which obstacle species can be purged, freeing the land for industrial exploitation. The profit motive is overwhelming; the resources at issue are worth trillions of today's dollars annually. An engineer who can target species on demand can obviously target humans, or even subsets of humans, if he wants to. Black markets by definition are not subject to regulatory scrutiny, and of course tend to be populated by unsavory and low characters. The environmentalist extremists (many of whom are well-financed or independently wealthy) will retain the services of some of these black market operators, to "fight back" (as they see it) on behalf of the species being targeted for/by the corporations. This will probably culminate in a doomsday bug.
Note of 2001-Sep-3/4: the black market in genetic bullet engineering will spring from a white market. Invasive, disruptive, ecologically alien species (zebra mussels and killer bees, for example) will be controlled with this technology.
Note of 2005-Mar-29: There is probably a race underway. The question is, will humanity develop technology, particularly artificial life that is conscious, before a hostile alien civilization wipes out life on earth using superior technology. Humanity has been advertising its technological birth to the universe in a radiating sphere of eletromagnetic transmissions (mostly mass media) and pulses (particularly, nuclear detonations). That sphere currently has a radius of about 100 light years, a region of space that, with luck, does not contain any hostile technological aliens. But it is probably only a matter of time before the transmissions are detected by that sort of alien. Once it does, the clock is ticking in the other direction, since they can't reach us faster than the speed of light allows. The reason a hostile alien would seek to destroy us is because they expect that we will eventually develop technology that threatens its own designs. Thus our survival depends on developing that technology before they can stop us. That technology is our only hope for survival. And conscious artificial life is an essential part of that technology. (The foregoing conception of hostile alien life is a regurgitation of the view of Stephen Hawking of Cambridge University. The idea of what to do about it is my own.)