New take on Google's "personal time"

As almost everyone knows, Google started an unique trend in the industry. At first they allowed, then encouraged, and now they require their employees to put aside one day of the week to work on their own pet projects. It was a revolutionary idea that attracted two kinds of reactions. The starry eyed programmers everywhere said what a noble company Google was, they had the employee's best interest in their heart. As we all suspected, Google has a heart of gold. On the other hand, industry veterans like Steve Balmer mocked google's personal time concept
calling it naive and insane.

However what most people missed is that the motivation for this concept was neither altruistic nor misguided naivety. It was a carefully calculated, but bold move, that any entrepreneur would appreciate. Think what happens in most companies that attract great people. These people do their day job to earn a living and spend the rest of their free time thinking up other great ideas. If they come up with a hit, they take off, start their own venture and eventually make millions or move on to the next big thing. The company where they were earning their living didn't really gain much from this.

Companies do try throwing their lawyers at such ventures, trying to claim the intellectual property, but except for the fear factor they create, they rarely succeed. So how do you take advantage of such great ideas fomenting in the brains of their employees ? Why, encourage them to work on these in company's time. This is exactly what Google is saying, and I don't think its as evil as it sounds. If I were working for such a company, I would probably work on less spectacular ideas during the personal time, and still keep the more spectacular ones for after work, in the quiet comforts of my basement, ensuring no evil hands can ever reach them ...

It would be great to hear opinions of new and old Google engineers about this :)