In homeopathy, QL has zeroed in on one of the most problematic parts of alternative medicine, no doubt. And Dr. Dodge's and Somol's answers are eloquent and insightful.
Like some of the commenters, I feel much discomfort with the idea of homeopathy, mainly in that it so seems to fly in the face of very hard science we now know (basic physics and chemistry). Fnarf is right in that there is no way this can work if you know anything about Avogadro's number.
And yet I feel somewhat compelled to maintain an open-mind for 3 reasons:
1) it's extremely cheap (in the scope of "expensive" scams this ain't it)
2) the scientific literature on homeopathy is not quite so damning as other commenters have portrayed it. While it is true that there have been a lot of negative research trials, there have been enough positive ones to prompt me to stay at least somewhat open minded (especially to treat benign conditions for which other therapies don't work all that well). Below I've listed some examples of such possibly suggestive research which is still kinda paltry and so not at all clear cut (I really do remain very very skeptical) (but still it is a bit more than you might expect just from publication bias and researcher bias alone so maybe this does warrant bigger, better, more expensive studies before we completely dismiss it):
--- Homeopathy for childhood diarrhea: combined results and meta-analysis from three randomized, controlled clinical trials. Pediatr Infect Dis J. 2003 Mar;22(3):229-34.
--- Evidence of clinical efficacy of homeopathy. A meta-analysis of clinical trials. Cucherat M, et al. Eur J Clin Pharmacol. 2000 Apr;56(1):27-33.
--- Homeopathy for postoperative ileus? A meta-analysis. Clin Gastroenterol. 1997 Dec;25(4):628-33.
3) And lastly, homeopathy is incredibly safe.
I'd say that the argument that it's dangerous because it leads people to forgo more effective treatment doesn't hold much water here because: 1) most of the time it's used for relatively benign conditions for which there are no better treatments and 2) when it is used by people who are forgoing "conventional" treatments, even if homeopathy were banned those people would probably not turn instead to the "conventional" treatment. Instead, they would likely just get no treatment at all or seek other equally "unconventional" treatment. In this case, homeopathy's not making them turn away, it's deeper factors at work. This type of situation, however, is the best argument for better enforcement by the FTC/FDA to root out overly rosy advertising claims about homeopathic products, to protect the public from being too misguided.