I agree, I've had to deal with this issue many times. I think it has happened at least 4 times in the last year. A few times I had to manually go in and start d

I agree, I've had to deal with this issue many times. I think it has happened at least 4 times in the last year. A few times I had to manually go in and start deleting old kernels because it had completely run out of space, so apt couldn't do anything without crashing. I eventually set up a cron script to regularly delete everything except the last 3 kernels. I think this should really be the default behavior. "Save all the old kernels until you run out of space and everything crashes" doesn't sound like a very sane default.