The case for Google building a PC

Is Google building a PC? Is that the logical end to its current expansion?
Think about it. It has loads of cash. It's been creating loads of PC software tools to rival Microsoft, a company it's at war with (see Damien's post about dumping Microsoft and using Google docs). And now it's ramping up its involvement (or maybe technology exchanges?) with hardware manufacturers such as Apple. So why not make a low cost computer itself? It, uniquely, has the positive brand power to do it.
The €399 G-Mac? Or even the 'GC'?

ps I know that this has been speculated on before. But the timing seems better now.