This weekend's goal was to install Yellow Dog Linux on my Cell blades (those that have drives, at least). The winning solution was found by Bartek Kochan.
QS20 blade(s) with drive and controller card.
IDE to USB widget
Yellow Dog Linux DVD
Prerequisites: experience installing Yellow Dog Linux on a PlayStation3
Pull the drive out of the QS20 blade, attach that drive to the PlayStation3 with the usb<->ide widget. Install Yellow Dog Linux. When asked which drive to use for the install, select the ide drive. Once the install of Yellow Dog Linux is complete, stick the drive back into the QS20, put the QS20 back into your chassis, and repeat for all your blades.
Part 2 ... for those of us that have QS20 blades that do NOT have drives and/or controller cards.
I suspect I'll get to learn about PXE booting
In any case, I should have three Cell blades up and running tomorrow.
At this point I need to order another voltage regulator so I can power the second pair of power supplies. Then I should be able to get six Cell blades running, possibly seven. Though it seems one of my blades has problems, won't talk to the chassis, so I may have only six that work.
I'm also going to ignore all the warnings about QS20s not working with any other type of blade, and see if I can get an HS21 running at the same time.