[spjonez]

Running OpenELEC with /storage on USB is very fast, probably more of a performance gain than overclocking. Of course this depends on the quality of your SD card, unless you have the Sandisk ultra/extreme cards you will get a very nice boost from this. They seem to be the only ones that perform near the same speed.

Easy steps to setup OpenELEC via USB if you're on Windows:

1. Download the latest OpenELEC image, if you're moving your install from an existing SD skip to step 3
2. Install to your SD card.
3. Non-Linux users, download a live Gparted image (http://gparted.sourceforge.net/liveusb.php) install it on a thumb drive and boot into it from your computer
4. Open gparted
5. On your USB hard drive, delete all partitions so its empty (this will delete all files!)
6. Select the /storage ext4 partition from your SD card, click copy
7. Select the empty space on your USB hard drive, click paste
8. Optional, resize the /storage partition on the USB hard drive, you probably can't do this step later so I went with 32gb just in case
9. Create a new partition filling the remaining space on the USB hard drive for shared storage, I chose NTFS since all my desktops are Windows
10. Delete the /storage ext4 partition on the SD card, leave the unpartitioned space empty
11. Open the cmdline.txt on the fat partition of the SD card, change the line to disk=/dev/sda1
12. Plug in SD and USB hard drive before powering on the Pi
13. Allow a moment of silence while you sit in astonishment at how fast XBMC is now

I chose to keep the OS on the SD, it's loaded into RAM so you will not see any performance gain in XBMC from running it off USB. This allows you to continue using the normal update process as well.

With the tweaks I included on page 1 and using a USB hard drive for storage, I can use the Quartz Reloaded theme (https://github.com/pecinko/quartz.reloaded), Showcase Lite view type, and when I mash arrow keys in TV or Movies the UI is very smooth.

Hope this helps!