For Sun Microsystems (JAVA), it has come down to this: the stock is now trading for the net value of the cash and investments on its balance sheet.

As of September 30, the company had $2.63 billion in short-term cash and investments. Add in $490 million in long-term investments, and back out $694 million in long-term debt, and you get net cash of $2.486 billion.

JAVA shares today have dropped another 34 cents, or 9.2%, to $3.38. It’s current market cap: $2.49 billion. Since announcing the headcount reduction plan, the stock is down 17%. Ergo, you in theory could buy Sun today, pay off holders and the debt with the existing cash, and get the entire company for nothing.

Now, I know, I know, that does not include the costs of the company’s plan to cut 5,000-6,000 jobs. So there’s actually less cash to go around than meets the eye. Nonetheless, the stock’s ongoing swoon is a startling reminder that any stock not trading at zero can always go lower.