Apache Guacamole (Clientless remote desktop gateway)
Supporting standard remote protocols like VNC, RDP, and SSH.
https://guacamole.apache.org/

Google’s Dig webapp (DNS lookup)
Tool for interrogating DNS name servers.
https://toolbox.googleapps.com/apps/dig/

Obsidian
Flexible writing application using markdown, a non-propietary language.
https://obsidian.md/

Kompose
Docker compose to Kubernetes/Openshift conversion tool.
https://kompose.io/
$ kompose convert -f compose.yaml
$ kubectl apply -f .
$ kubectl get pods
NAME READY STATUS RESTARTS AGE
frontend-591253677-5t038 1/1 Running 0 10s
redis-leader-2410703502-9hshf 1/1 Running 0 10s
redis-replica-4049176185-hr1lr 1/1 Running 0 10s
While you can get away without a version tag in your compose.yml file for modern docker ce, you will get a complaint from this tool unless you put in a version: tag