How to Instal Ubuntu without a Live DVD or USB Drive

So my sister's Windows computer was having performance problems for a while.. basically its difficult for the average user to maintain a computer on their own.. and I just have the patience to run tools like Ccleaner and a virus scan. So after the 3rd or 4rth maintennance run i gave up and decided to install Ubuntu on it.

I'd already got my mother and several coworkers onto Ubuntu in the past, so this would be a simple enough thing to do. So I redeemed about 20gigs of free disc space for the task, then got out my trusty live USB drive and rebooted.

The laptop turned out to be too old to support USB boot options. I hadn't burned an optical disc in ages.. and was pretty sure i had no blank discs anywhere in the house.

So now I was stuck. On a hunch, I googled 

"How to Instal Ubuntu without a Live DVD or USB Drive"

That got me to this helpful Ubuntu forum post - 

http://askubuntu.com/questions/484434/install-ubuntu-without-cd-and-usb-how

Heres what you do:

1. Download Unetbootin from here. Its a tool that creates a bootloader with two options -
   Boot Windows  or Unetbootin.
2. Run Unetbootin. 
3. Now, from the drop-down menu under Type: select Hard Disk.
4. Next select the Disk image from which you want to install Ubuntu(or any other distro). Browse to the directory where you downloaded the iso file of Ubuntu.
5. Press "OK"
6. When you reboot, you will get a menu like this:
   a) Boot Windows
   b) Unetbootin
7. Select Unetbootin and you will get the "Try" or "Install" option there.
8. The rest is the standard magical Ubuntu installation process. I just have the habit of assigning a swap drive and root drive myself. And then letting it do its thing.

My sister is now on Ubuntu too.