For an army of workers who wear wingtips like combat boots, Hickey Freeman suits like flak vests and clutch Samsonite briefcases like duffle bags, the BlackBerry is as much a phone as a sidearm: reliable, always on the hip, but ultimately, too weak for the real action. Delivering presentations the sales equivalent of trench warfare requires the big guns. A chunky laptop is usually par for the course. Research in Motion set out to change that with its $200 BlackBerry Presenter. The tiny, palm-sized brick takes the place of a much larger laptop by allowing the everyday BlackBerry to serve up PowerPoint files to a projector or TV screen, wirelessly. We took the new device through live fire training to see whether it could really pull it off.