It shouldn't come as too much of a surprise that RIM is doing pretty well even in the face of an economic downturn, but it looks like it's been doing really well -- at least according to Fortune, which has just named the Canadian company the fastest growing firm in the world. That's apparently based on a combination of profits, turnover, and investment return over three years which, in RIM's case, translates an 84% growth in profits in the past three years, a 77% growth in revenue, and a total return of 45%. It's also actually the first time RIM has made the list, although that's at least partly due to the fact that Fortune didn't include non-US firms last time around.