Gmail-python is a project mainly written in Python, it's free.
Python module for accessing web interface for GMail
GMail-Python is a Python module for interacting with GMail's web interface in Python.
Get all messages in the inbox, and print their info
import gmail.GMail
username = "bruce.lee"
password = "kapow!"
session = gmail.session(username, password)
session.login()
messages = session.get_messages()
for message in messages:
print "-" * 50
print "Message Details:"
print "From: %s" % message["from_name"]
print "subject: %s" % message["subject"]
print "is unread: %s" % message["is_unread"]
print "message URL: %s" % message["message_link"]