Which can afford it? All of them!
Corporations are taxed on profits, not on revenue. So anyone who will be taxed by definition has money, because they made a profit. Remember, they can write off just about anything that is involved with the operation of the corporation. So if they're losing money, they don't pay taxes.
Contrast that against income taxes, which are mostly (with the exception of a couple of write-offs like mortgage interest) on revenue.
An interesting thought experiment... what if income tax was treated the same way as corporate tax... you can write off ANYTHING that has to do with operations (living your life). That would be quite a stimulus, because it would encourage people to spend on all sorts of things, rather than just on real estate.
Your needs for 1000+ uniques are minimal. If I were to do it, I'd get a shared hosting account someplace and move on. Shared hosting can handle *way* more than that.
But if high availability (limited downtime) is part of the requirements, I'd say go out and buy an F5 BigIP. You plug your internet in the front, your machines in the built-in switch, configure your domain names in it using the web interface, and you're done. Set it to do service-checks, and it'll automatically pull out of the pool any machine that fails or that you take down for maintenance. So you get full up-time so long as your power and network don't fail.
Yes, you can get the same functionality using Linux HAProxy. But you sort of need to understand what you're doing. Reading the way your question is asked, I suspect you're learning this, and do you really want to make the mistakes on a real live project? Just go with the appliance until you have a solid understanding of what you're doing. Shoot -- I have a good solid understanding from years of experience, and I still use the BigIP when I have a budget (and HAProxy when I don't). It's just easier, and I can move on to more interesting problems with my time.
Once you've got this setup, set up a cron job to rdist the site to all the machines so that all your data is always on each machine. If you've got a database, you have some choices. For completely static data, I like to have it replicated to each machine, and have each web server just query localhost. If it's dynamic, have a replicated pair. At your levels, that can exist on the web servers.
I really dislike the cross-mounted disk architecture of traditional cluster solutions, because there are too many shared components. Each of those multiplies your possible points of failure for your whole setup. Better to keep everything completely separated, so if one component fails, that whole machine just drops out and the site keeps working because of the load balancer and because each machine can operate by itself.
When I changed to the Silverlight client, the quality improved, and I got to run it on my Mac too. What's not to like?
I love open source too... but you do yourselves a disservice when you fail to see the real reasons. They've got to stick to a DRM solution in order to get the film distributors to let them do rentals this way. It's how the distribution houses know who to pay royalties to. Without DRM, the major distribution houses would just say no. It's not Microsoft or Netflix forcing DRM on us -- it's the studios. And for a rental product (as opposed to a purchased one), it sort of makes sense.
Netflix planned this change for a year or more in order to deliver to the Macintosh market. They talked about it in their blogs and such -- they were just waiting for the Mac version of Silverlight to make it happen. I was sort of annoyed that it took so much longer than originally projected.
And for me the result has been significantly better quality with almost no re-buffering ever.
A computer without COBOL and Fortran is like a piece of chocolate cake without ketchup and mustard.