Apparently Cold-FX works according to Health Canada. Clinical trials do exist that strongly suggest that Cold-FX, a ginseng derived therapy, prevents and cures colds and flu. Health Canada has given it a natural product number and therefore has approved it's claims as stated on the bottle. CV-technologies, the company that pimps Cold-FX, had a massive stock price jump upon the news of the approval. Don Cherry, once up for 'best Canadian of all time' or something like that, pimps for Cold-FX (and Quiznos) and according to this article I just read perhaps physically intimidated Stephen Harper (link to info on his podcast) into issuing the natural product number to Cold-FX and CV-technologies. Awesome.
CV-technologies also has Remember-FX, which apparently also has passed muster on a clinical trial, although I can't find it.