I can name only one: mobile. OTOH Ballmer spearheaded Azure and Office/Exchange as a service, both of which are the major reasons why MS is a trillion-dollar company on an upswing today. No amount of Satya would save it, if Ballmer didn't beat the internal Microsoft "deep state" into submission on Azure and SaaS first. And a serious beatdown was required before Office and Windows apparatchiks received the message.
I think you're confusing him with Gates. Although Ballmer did refuse to buy Google when he could. Would have been a drop in the bucket. I forgot, BTW, he also spun up the ad and search businesses: the only reason there's any alternative to Google at all.
Arguably, if he would've bought Google, we wouldn't have the internet as we have it today: people would've payed for search, as for the OS and Office suite: $10 per 1000 queries per month.
