Ok, I'm curious. I'd like an explanation as to how cutting the top rate of tax is going to motivate ANYONE to do ANYTHING else. I've never heard a decent reason why cutting the tax rate would help.
Let's say that in some fictional country you're earning, I dunno, $200,000 a year, and are taxed 40% a year (for the sake of easy maths, we'll say that covers everything). This means you take home $120,000 every year. Now, let's say your rate is halved. You take home an extra $40,000 a year... but how does that motivate you to work harder? If anything, it allows you to work a bit less and still earn the same amount. Sure, you could earn more money if you worked harder, but it was exactly the same under the old system.
I suppose the argument that's trotted out is that it'll allow small businesses to employ people. Well... using basic economic theory, it won't. The calculation you should do before employing someone is how much they'll make for you vs how much they'll cost, not how much money you already have in your bank account.
And let's go back to the $200,000 example. What are you going to do with your extra 40k a year? Are you going to be able to spend it all on consumer goods and reinvestment? Generally not. Generally it'd just be thrown on the pile in your bank account, where it isn't going to be doing the wider economy much good.
As a final point, I propose that, when society has become too unequal, an economic crash is inevitable. After all, CEOs aren't going to be buying thousands of consumer goods from each others' companies.