I never got own the original iPod. My first iPod was the mini. However, this fully functional iPod webapp made by Pritesh Desai will bring nostalgia to original iPod owners. To use the app, drag (rotate) the clickwheel, as you would do on a real iPod. The iPod for browser was made using HTML 5 and CSS. View the story behind it here.
The app also works well on the iPhone browser. Just a matter of tweaking to make it fit the screen.