It even works some from my Android mobile's browser.
Can be useful to write and run snippets of code on the go :-)
Also to run code from your desktop / laptop, whether or not you have Go installed locally. All you need is a reasonably modern browser and an Internet connection.
The Go Tour - tour.golang.org - also lets you do this, with the added benefit that you can modify their examples and then run them.
- Vasudev Ram