(taken from http://www.mydigitallife.info/2006/10/18/bypass-and-crack-megaupload-and-sexuploader-download-slots-and-size-limit-with-alexa-toolbar-hack/)
- Download and install the User Agent Switcher extension for FireFox.
- Restart the FireFox web browser after installation ended.
- Go to Tools -> User Agent Switcher -> Options.
- Then click on User Agents and then click on Add.
- Key in the following information:
User Agent: Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1; Alexa Toolbar)
- Exit by clicking on OK twice.
- Whenever you want to download from MegaUpload or SexUploader, go to Tools -> User Agent Switcher and select MegaUpload as FireFox’s temporary user agents.
- After downloading the files, you may want to switch back to original user agents, by selecting Default.