Examples

$ s3-secure summary
Determining bucket security-related settings...
+----------------------------+------+------------+
|           Bucket           | SSL? | Encrypted? |
+----------------------------+------+------------+
| a-test-bucket-in-us-east-1 | yes  | no         |
| a-test-bucket-in-us-west-1 | no   | no         |
+----------------------------+------+------------+
$

There are --ssl no and --encrypted no filtering options:

$ s3-secure summary --ssl no --encrypted no
Determining bucket security-related settings...
+----------------------------+------+------------+
|           Bucket           | SSL? | Encrypted? |
+----------------------------+------+------------+
| a-test-bucket-in-us-west-1 | no   | no         |
+----------------------------+------+------------+
$