"In play" is day-trader shorthand for the names everyone is watching today: something has happened, volume is pouring in and the price is moving. This screen lists stocks on the Toronto Stock Exchange up or down more than 3% today on at least twice their 21-day average volume, with an average true range above 3% of the price, so there is room to trade. The heaviest relative volume comes first. Prices are in Canadian dollars, and the list covers TSX-listed stocks with at least C$1 million in average daily trading value.