Thanks to an apparent lack of clean-up on iTunes' part, many users have oodles of disk space that is being unnecessarily occupied by old iPhone and/or iPod touch software updates.
As described reader Doug Eldred:
"I have 10 files, ranging from 150 MB to 250 MB for my iPod touch, and much smaller files for two other iPods, one of which I no longer own. They total well over 2 GB! Now, if I really need to keep restore files back to version 1.0, I will, but I'd be happy to pitch the older ones." … Read more