finally, the micro-cap firm prana biotech. this is the past month, and look at the action this stock has seen in the past two days-- more than doubling. up 36% just today. it received positive results on an alzheimer's drug. but the stock has seen the action before. in april, shares doubled in a day thanks to news on the same drug. two months later, the stock dropped back down. and that's tonight's "market focus." >> tom: going big is in fashion for gold investors. small mining stocks did well last year as gold prices shot up. but bigger, more established names are doing better this year. tonight's "word on the street"-- "gold." alix steel is a reporter at thestreet.com. alix, always nice to see you. what qualifies as a big gold miner. >> you have to think big. we're talking gold producers that produce about one million plus ounces of gold a year. the biggest company in the whole world produces more than 7 million ounces of gold. >> tom: and they have production. they're not speculative, still looking for the stuff. they've fou