[guptaneil]

By time value of money, I meant that present value of money is greater than some theoretical future value. So although your laptop costs about $11/month spread out over 4 years, it's still a $558 investment upfront, at which point it's a sunk cost. On the other hand, you could just invest $20 and invest the remaining $538 in something else that might offer greater return. Depending on the kind of interest rates you're able to get, it might be better to just put the rest of the money in the bank and let it earn you interest. There's also less risk. If something better comes along next year, you can easily switch with little to no loss.

I am assuming that you are not using a payment plan to buy your netbooks, and are actually purchasing them all upfront.

[TomOfTTB]

I see your point now. And on the interest point I'd concede it but even if we got a monstrous return on that money I can't see it making much difference.

Though another issue is with the Google Chromebooks you have to sign up for a 3 year contract (though you obviously wouldn't have known that when you made your initial comment): http://searchengineland.com/google-chromebooks-out-june-15-3.... So on being able to change course that's not as possible as it seemed when you made your comment.