You might want to check out TinyCore Lunux. In 10Mb ISO you get a functional image with GUI and thousands of apps in the repository including Chromium and Firef

You might want to check out TinyCore Lunux. In 10Mb ISO you get a functional image with GUI and thousands of apps in the repository including Chromium and Firefox that can run in as little as 39mb of RAM. I run multiple TinyCore VMs in VirtualBox for safe browsing in the darker corners of the Net.