Debian Live released for PS3, so download away!
What is Debian Live? You've got me there, but what I do know is that it's a highly respected Linux engine... more so than Fedora Core and... that other one. What's more is that this system/engine/thingy is being distributed via .iso, so download it now, stick it onto a CD and load it right onto your PS3 with little to no trouble and/or effort! That's... how it works, right? No? Hmm, I really need to learn how to do this.
Anyway, on the Debian Live for PS3 site, there's a list of all the prompts you can use as well as parameters you can set (login, password, etc). We're linking you directly to their site because it makes a lot more sense than if I tried to describe it. Also, if you have any trouble, visit the About page and see if anything there helps you out -- I couldn't find a specific set of instructions (probably because this is supposed to be easy), but it seems like they go into more detail here. If anyone gets this up and running, tell us how it stacks up to the other programs available.
