Wordpress overload?

I've noticed that a lot of blogs using WP crash when traffic spikes, however other sites like Techcrunch dont. Do they use a special version of the software? Is it available to everyone?

 

They have a host that is good. They pay per gb of bandwidth.

 

I think it also has to do with using way too many plugins. Some of them are total resource hogs.

 

Any idea what those popular plugins are that uses a lot of resources?

 

Someone here reported that the star rating for posts plugin (I think there's only one?) really killed his site once the number of visitors increased. I'm pretty sure the video player plugins do the same.