This is a simple script in Perl that will clear out an Amazon SQS queue.
I've found this useful since the alternative is to delete and re-recreate the queue with the same name.
./clearsqs.pl --accesskey <access key> --secretkey <secret key> --queue <queue url> [--dump]
--accesskey - The Amazon account's access key
--secretkey - The Amazon account's secret access key
--queue - The absolute URL to the SQS queue
--dump - Writes each queue value to stdout