I don't know if I would go as low as net-net (current assets less all liabilities). The building is probably worth approximately what they paid for it. There is probably some furniture and computers and things that may or may not be worth their carrying value (depreciation is supposed to account for the decline in resale value).

It is always a bit sad when a company is worth less than the sum of its parts. I don't think Zynga is quite there, yet, but I don't think it is worth very much unless and until they sit down and learn how to run a business. I won't be investing in it.

You are correct that short term investments would be stocks or bonds or term deposits or any other highly liquid assets. Generally, they are as good as cash.