Actually, I should have spent about 30 more seconds on Google ...
http://www.archive.org/help/abouts3.txt says I can use the s3cmd tool:
sudo apt-get install s3cmd
And then edit the configuration file, so
~/.s3cfg looks like:
host_base = s3.us.archive.org
host_bucket = %(bucket)s.s3.us.archive.org
access_key = key
secret_key = key
use_https = False
verbosity = WARNING
Then use the following script to upload everything to archive.org:
BASE_HEADER=something-$(date -u +%s) #something that should be unique
echo Converts to PDF and uploads the contents of a directory given as the command-line argument.
echo Now converting PDF to JPG
for file in `ls $1/*.pdf`
convert $file `echo $file | sed 's/\.pdf$/\.jpg/'`
echo Listing JPGs: #make sure the conversion worked
echo Making the bucket...
s3cmd mb s3://$BASE_HEADER
echo Sleeping...#sometimes it takes a moment to be processed on their end
echo Uploading files...
for file in `ls $1`
s3cmd put $1/$file s3://$BASE_HEADER/$file
It's run like