Software Library
archive.org
The Internet Archive Software Library is the ultimate software crate-digger's dream: Tens of thousands of playable software titles from multiple computer platforms, allowing instant access to decades of computer history in your browser through the JSMESS emulator. The intention is to ultimately...

This is a huge collection of classic games, software and demos that can all run right out of your browser. There are a lot of different collections to browse through. If you have some time, it’s worth checking out.