1. Install Flash 9
2. Go to http://dougmccune.com/blog/2007/07/25/coming-to-flexcamp-at-adobe/
3. Try to select some text or scroll the page
Flash is sending WM_USER+1 messages like crazy. We'll need something like WebCore's PluginQuirkThrottleWMUserPlusOneMessages quirk.
Luckily, this only happens with Flash 9, not Flash 10.
Plug-in support has been removed from WebKit.