S3 Error: The difference between the request time and the current time is too large

The time on your local box is out of sync with the current time. Sync up your system clock and the problem will go away.

For those using Vagrant, a vagrant halt followed by vagrant up worked for me.

The clock is out of sync.

I followed the steps in this post to get it working again, but also had to run the following command.

sudo ntpdate ntp.ubuntu.com
sudo apt-get install ntp

If at any time you get a message saying the NTP socket is still in use, stop it with sudo /etc/init.d/ntp stop and re-run your command.