Can't figure out if your account is in the developer sandbox or not? Sometimes the "Welcome to the iGoogle Developer sandbox" message is obscured. Sometimes developers are confused about the behavior of the http://google.com/ig/sandbox page (which acts as a toggle, not just a redirect). And sometimes sandbox features aren't working properly, so that even if you are in the sandbox, it looks like you aren't.
Here's a small gadget to provide a little heads up on the sandbox status. If you're in the sandbox, it lets you know and gives you a quick way to leave. If you're not, it gives you a quick way to enter. And, finally, if it thinks you are in the sandbox, but features don't seem to be working, it tells you that, too. Think of it as your personal sandbox valet.
The exact behavior relies on the current rollout of features (and using the .com TLD), so it will likely need an update down the road as launches occur. Please test it, add it to your pages, and check the status message if things aren't working properly.
For questions and comments, feel free to add to this thread in the forum.