I always thought the punishment suggestions were dumb too. Damages? Please. They have so much cash it would only hurt for that quarter. Plus they would just donate an "equivalent value" of Microsoft software to schools, ironically furthering their proprietary lock-in. Breakup? Yay, now we have four separate monopolies.
I always thought the best solution would be to require them to open their secret file formats, APIs, and network protocols, and invalidate their software patents. The market would take care of the rest from that point.