Not all hacking is bad. Sometimes hacking can be used to enhance the features of a product, instead of perform malicious actions.
One of my hobbies is photography. Today I downloaded the "Canon Hack Development Kit" (CHDK) for my Canon Powershot S2 IS.
After a couple wrong versions, I finally downloaded the correct version for my camera, and was up and running.
The way the CHDK works is pretty ingenious. The CHDK software is loaded into your camera's RAM by tricking your camera into thinking it's loading a firmware update. However, instead of loading a firmware update, CHDK is temporarily loaded into memory much like running an application on your computer or phone - it's not loaded into memory the next time you turn off and turn back on your camera.
The features enabled with CHDK are pretty amazing. My "point and shoot" camera now has some features which aren't available on my wife's professional camera, such as motion detection or extended time-lapse photography of up to 64 seconds (some cameras allow up to 30 minute time lapse!).
If you have a supported camera I highly encourage you to check it out.