Daaark, it might just be me, but I think it's misleading to say "you can't do it without Sony's say so", because that's not strictly true in all cases. It is entirely possible to write raw C or C++ using PSL1GHT or the leaked v1.92 of the official PS3 SDK and then compile and run programs on the Playstation 3 natively.
I'm a little behind on my PS3 homebrew scene-ology, so I'm not sure if the private key used to sign official software is still a valid means to sign your code to run it on the Cell without modification. IIRC this is a vulnerability that isn't exactly patchable without invalidating all prior officially licensed software on the market in one fell swoop. Maybe this is something the OP can look into.