First thing: I am not asking what software I'm supposed to use. I already know the answer: Ghost (proprietary), Clonezilla, and dd (if I'm careful).

What I really want to know is if it is possible to (essentially) bit-for-bit clone my entire installation (OS, installed software, activation(s), etc.) to an external USB hard-drive, and then boot off of that (if I need to, I know how to edit BIOS settings and use Plop boot manager), and work with it day-to-day as if there was virtually no difference from using my internal HDD now.

Again, I'm not asking how to install Windows to an external (because I know I'd need to do some special workaround), I'm asking if I can clone everything and boot off of it.

In case you're wondering why I'm going to this trouble: I'm using a Lenovo Essentials laptop that has an unmodifiable partition table (due to recovery crap), and has all 4 of its partitions spoken for (3 primary, one extended, cannot change the extended). Anyway, my thought is that if I can clone everything and boot off of it when I need to, and just have a Linux distro on the internal HDD, then that could work.