A typical Debian/Ubuntu installation takes at least 15 minutes, and you have to answer a lot of questions along the way. Yet a VPS service on the Web is able to deploy a ready-to-use Linux server in under 1 minute.
I'd like to have my own prepared image file with pre-installed packages that I can plug straight into VirtualBox, or upload to a hosting service, and -bang- there it is, without the 15 minute manual installation or answering any questions. It's just ready in as little time as possible (like a minute or so).
How can I achieve this?