Windows
In Korea one must use Windows. All internet banking sites have ActiveX controls, and every file anyone sends you is a proprietary .hwp format that is only viewable with a Haansoft Office Suite. There is a Linux version of the Suite, but it is shit.
Haansoft Office allows people to save as a .doc, which one can open in Libre/Open office. But the formatting always looks like shit. And it allows people to save as .pdf, which is fine for viewing, but less fine for editing. But the bigger problem is that no-one does this. As many times as you as you ask someone to resend something as a .doc file, or god forbid, an .odt, you more likely get offered a pirated version of Haansoft Office.
So you are forced to run a virtual machine for just internet explorer, Haansoft Office, and perhaps iTunes.
Fittingly, Haansoft Office frequently crashes windows guests of any flavour in an Ubuntu hosted VirtualBox . So writing grant proposals, which must be submitted in .hwp, I spend days kicking my furniture.
Or I did. Not any more. Wine 1.3, which is shit for ActiveX, runs Haansoft Office 2007 out of the box. No crashes, and none of the crappy interface of the Linux version.
So using Wine for Hangul 2007, the only thing you need a virtual box for is your ActiveX. And who needs iTunes, licensing issues make it useless in Korea anyways. Sadly every website in Korea uses ActiveX.