I'm sorry, let's try that again

My wife was using her iBook tonight when alla sudden Apple Mail said the Inbox was read-only. Wha'? Couldn't remove or create files from the Terminal, and /var/log/system.log showed this message:

kernel: disk0s3: I/O error
kernel: jnl: do_jnl_io: strategy err 0x5

A lot of scary messages turned up in the search results about replacing hard drives, memory and mainboards, but I decided to try a fsck for the fun of it. Splat-s sent the Apple into single-user mode, and then fsck -f -y said the volume had been repaired successfully. Reboot and things look good: I can create and remove files, and Apple Mail is fine. Interestingly, the disk said it had an extra GB free compared to before the reboot.

The drive is old, and may still need replacing. Thankfully, I've set up a cron job on this thing to rsync the home directory daily to another machine.