I've heard a lot of good stuff about amazon web services.
But for 95% of us here, we don't need cloud computing, it does nothing for us that normal hosting won't do. Cloud computing is great for two things (1) LOTS of sporadic (non-regular) computer processing needs, or (2) extremely rapid unplanned growth.
If you have a really complex app that takes a long time to run and maxes out your server while it's running, that's perfect for cloud computing, especially if you don't do it all day but just at certain times.
Or, if you've got a killer app that you just KNOW is going to go crazy in traffic (and thus processing need), like the next youtube or facebook, cloud computing allows you to "upgrade" your capacity nearly instantaneously. Something you couldn't do if you all of a sudden had to buy three times as many servers as you already have and deploy them quickly -- no way that can happen quickly under normal circumstances. Cloud computing makes it possible.
But really how many of us discover the next facebook? And have that rapid of growth? My own personal network has seen growth anywhere from 20-50% a month during the last year, which is phenomenal, but I have still been able to keep up with it relatively fine so far.
Here's a site that is a great example of something for which cloud computing is spectacular:
www.animoto.com
It's a web app that lets you input your own still photos, and add your own music or music from their library, in which it dynamically generates a video using your photos so that they change with the beat of the music, and have special backgrounds etc. Really a cool app, and if you play with it you can imagine how much processor time it uses.
They run completely on AWS EC2 and there is no way they could have kept up with the hardware demands of how popular they have become so quickly without a cloud computing environment.. because their app is so heavy on the computing.
But for 95% of us here I think it's like hunting with a bazooka -- overkill.
