Amazon S3 crossdomain.xml

Step1.
Use S3 Firefox Organizer to login your s3 account

Step2.
Create a [bucket](folder under your s3 root)

Step3.
Upload crossdomain.xml to this [bucket]

Step4.
Right click the crossdomain.xml and select "Edit ACL"

Step5.
Make "Everyone Read" checked



Step6.
Now you can access crossmain.xml

http://[bucketname].s3.amazonaws.com/crossdomain.xml