In fact this is a complete myth. Microsoft did not "keep Apple afloat." Not only did Apple have over a billion dollars in cash on hand at the time at the time, the Microsoft "investment" in Apple was a settlement for a long-standing lawsuit. Neither a rescue nor the Department of Justice had a single thing to do with it.
Die myth, die.
Absolutely; this is one of the most ridiculous yet widespread rumors of all...MS invested only a petty amount of 100 million for some cross-licensing deals, equivalent to a (very) minority stake in Apple, nothing else. With that, they also committed to continuing development of Mac Office for 10 years or so, a token well received by the market in those difficult times for Apple.
What, in fact, kept Apple afloat was the streamlining begun by Amelio and continued by SJ, after the disasters brought by Sculley and Spindler...