If your laptop is sleek and clean, and you've been looking down at those slightly dirty computers with dozens of "Docker", "Kubernetes", "VS Code" and other stickers, think again. Owners of those machines are starting to receive their ad revenue cheques in June 2020.
However, not all stickers tend to make money. "Git", "Bash" and "HTML5" stickers yield zero revenue, while "Geek Inside", "XML" and "IoT" stickers actually decrease potential revenues.
General recommendations of ad gurus are to ask for a contract every time some company hands out stickers at a tech conference.