After many earlier rounds of saber-rattling and FUD, Microsoft has announced that Free Software users -- including everyone who, like me, uses Ubuntu Linux -- are violating at least 235 of Microsoft's patents, though they don't say which ones. Microsoft are now threatening end users of GNU/Linux (that's you and me again) with lawsuits unless we pay them protection money. "Nice operating system you got there, it'd be a shame if something were to happen to it."
The Microsoft position is this: even if you don't use Windows, you still have to pay them as much money as they would have gotten for selling you a copy of it.
—Microsoft says GNU/Linux violates 235+ Windows patents, Cory Doctorow, BoingBoing, Monday, May 14, 2007
Microsoft did stop short of saying it would sue Linux users or its own customers: