As a web designer, I have a love/hate relationship with Adobe Flash. Flash can be a great interface for displaying interactive information. But Flash is also a security vulnerability, and Flash is a common format for banner ads.
My main beef with Flash as a user has to do with the banner ads. Flash banners are almost never served off the same server as the website they appear on. Instead, Flash banners are served by ad network servers that can dramatically slow the performance of the page you’re viewing.
Now, there is a plugin that gives you the power.
If you’re using Firefox, you can install FlashBlock, and on Safari you can install ClicktoFlash. Internet Explorer users can install Toggle Flash. Google Chrome users may have to wait a while for Google to implement plugins, though there are kludges for installing FlashBlock for the technically minded.
In both cases, the web pages you view will not load the Flash elements by default, instead displaying a button you can click to deliberately load the Flash element you want to see. By blocking the default loading of Flash elements, you minimize your security risk through the Flash plugin and should see an increase in page loading times.