Sure, but valuation should always exceed cash reserves. It's very odd when it does not. I think I recall that that SUNW (by then JAVA probably) was at one point valued below cash, prior to ORCL acquisition.

If Valve's secrecy is so good that they have (substantially more than) 30-500x cash stashed away in excess of their public valuation estimates, then perhaps I underestimate Valve's secrecy!

More likely, it was an obviously-humorous exaggeration, but I wasn't sure -- I am quite ignorant of the games industry. :)