The following article from the Montreal Gazette has some good points about investing in junior gold mining companies. The one point the media would like to impress upon you is how they are only valuable as a takeover target. But I would venture to say that a company which rebuffs hostile offers and lowballed bids is probably the better investment. It only stands to reason.
http://www.montrealgazette.com/touch/story.html?id=5982749