After playing around with the 8.04 ALPHA release I created an easy-to-install USB image for general use. Please test out the installation procedure and let me know if you have any problems:
(note: I updated this to point to the final stable release, version 8.04)
Step 1- Download the latest image:
Step 2- (This will erase the data on your USB device!) Plug in your USB device and unmount it. You can manually
create a partition for the Rescue Remix. You can even put that partition at the end of your device and create another partition at the beginning for storage or swap space. Make sure the rescue-remix partition is 166MB or greater or else the image won't fit.
Make the partition that will hold the image bootable (Use (g)parted or cfdisk); only one partition should be bootable or else that defeats the purpose.
If you put the storage partition after the rescue-remix image partition, you won't be able to access your storage partition from Windows-based operating system; It "just doesn't work."
Step 3- Write the image to the device:
If your device is the second partition on sdc, then you would run:
sudo zcat ubuntu-remix-804.usb.gz >/dev/sdc2
Step 4- Try to boot the device. If it doesn't boot, you need to put an MBR on the device.
sudo apt-get install mbr
sudo mbr-install /dev/sdc
And then reboot.
Again, if you have any problems, please let me know.