Snapshot_info is a project mainly written in PHP, it's free.
Script to display information about EBS snapshots
Written by Chris McDermott, AppliedTrust [email protected] v1.1 8/19/2011
This script expects an API key for Amazon's AWS EC2 service. It gets a list of all snapshots associated with the account (owner = self) and then analyzes the resulting list and prints out a detailed summary.