I don't really think Amazon wants these hacks to be applied, it would explain why they stopped us.
Not to mention -- USBNetwork, Rescue Pack, CRP, offer entry points into the OS (by design), the fonts hack is very fragile, KUAL and related hacks are mostly things that run decidedly odd stuff as well -- scripts for stuff that people wanted on the spur of the moment, cross-compiled binaries for just about anything, none of which are a candidate for Amazon inclusion.
No sure why they don't have decent screensavers, and we will probably never find out -- they aren't answering our calls.
Also:
Discussion about hacks belongs in the Developer's Corner. Moved.