CHDK is only possibly because of some characteristics in Canon's cameras. Once upon a time, a hacker decided to disassemble a firmware update file, and found out about a method to hook his own program into the cameras operating system. (If i remember correctly).
Something like CHDK might be possible on cameras from other vendors, but due to the complete different architecture it would need to be written from scratch again, and would therefore be a complete standalone project. You could of course try to find someone who is willing to do that kind of research, or start learning how to do that on your own.
And furthermore, please consider to refrain from abusing punctuation marks like that..
