Convert all Files to DNG for Space Saving Storage?

Has anybody used Adobe's DNG file formatting as a way to back up their RAW photos?

I have generated a lot of CR2 files over the years taking family photos and the RAWs take up quite a large amount of space. I was thinking that, since I probably won't be going back to edit years old photos, I would convert the photos to DNG to save space. The idea that this would save some hard drive space along with keeping some RAW-detail in case I want to ever go back.

Has anybody ever done this? Am I crazy?

Thanks for the input!