Of course, it's pretty easy.
Even Google's Android development package includes an emulator, there are others like NOX and many more.
Obviously you can only emulate certain things, you won't be able to make calls or use GPS receiver if you don't have it, although you can emulate it.
It can be emulated, in fact there are many emulators or images for virtualbox, just search on Google.
Of course, it's pretty easy.
Even Google's Android development package includes an emulator, there are others like NOX and many more.
Obviously you can only emulate certain things, you won't be able to make calls or use GPS receiver if you don't have it, although you can emulate it.
It can be emulated, in fact there are many emulators or images for virtualbox, just search on Google.