How to install OS X Yosemite developer preview in VirtualBox

# How to install OS X Yosemite inside VirtualBox
http://www.engadget.com/discuss/how-to-install-os-x-yosemite-inside-virtualbox-1rey/

Image: http://i.imgur.com/dc8qhut.png

Yosemite's first developer preview was released right after Monday's WWDC opening keynote. For the general public, an open beta will be available to download later this summer. However, for those who want a sneak peek at the new hotness, there is a way to safely install it without risking your machine, using the free and powerful VirtualBox application from Oracle.

Steps (most likely, the Engadget forums are going to bork the formatting, I'll drop in a Pastebin link below):

1. Download Yosemite from the App Store (or your favorite digital content distribution warehouse)
2. Open terminal
3. Run "gem install iesd"
4. Run "iesd -i /Applications/Install\ OS\ X\ 10.10\ Developer\ Preview.app -o yosemite.dmg -t BaseSystem"

Adding additional steps because certain files end up missing from above:
5. Run "hdiutil convert yosemite.dmg -format UDSP -o yosemite.sparseimage"
6. Run "hdiutil mount /Applications/Install\ OS\ X\ 10.10\ Developer\ Preview.app/Contents/SharedSupport/InstallESD.dmg"
7. Run "hdiutil mount yosemite.sparseimage"
8. Run "cp /Volumes/OS\ X\ Install\ ESD/BaseSystem.* /Volumes/OS\ X\ Base\ System/"
9. Run "hdiutil unmount /Volumes/OS\ X\ Install\ ESD/"
10. Run "hdiutil unmount /Volumes/OS\ X\ Base\ System/"
11. Run "hdiutil convert yosemite.sparseimage -format UDZO -o yosemitefixed.dmg"
12. Add yosemitefixed.dmg as a live cd in virtual box
13. Change the chipset of your virtual machine to "PIIX3"
14. Start your VM, open Disk Utility within installer and create a new HFS+ partition on the virtual disk
15. Install it!

Via: http://forums.macrumors.com/showthread.php?p=19191255