The need for human-animal clones was reached by expert British scientists in a recently released report. Apparently there are no laws against making human-animal embryos, yet (how did the Bush administration miss this?), in the US and Britain.
The scientists responsibly suggest that none of these embryos should be implanted in either a woman or an animal.
Implications - It seems we're heading closer and closer to being able to make real-life centaurs, minotaurs and mermaids. Although there is the possibility for creating human-animal hybrid embryos, it is very unlikely that any inter-species creature would be cleared for growth. If mad scientists existed in real life, they would most likely be all over this.