I have run into the same problem quite often and after some research, I found out that there is, in fact, a way to list all running resources using AWS GUI.
Follow the below-mentioned steps to list all the running resources in all regions using AWS GUI.
1. Go to your AWS Console and click on Resource Groups option
2. Select tag editor in the drop-down box
3. Specify all regions in Regions field and select the resource type as instances
Click on Search Resources
In case you want to achieve the same using AWS CLI, use the following command:
for region in `aws ec2 describe-regions --region us-east-1 --output text | cut -f3`
echo -e "\nListing Instances in region:'$region'..."
aws ec2 describe-instances --region $region