From 17 April 2008, RapidShare open "Happy Hours" service. But sometimes the bandwidth is full, so "Happy Hours" can't active.
"RapidShare Happy Hour Checker" is a tool that check whenever RapidShare Happy Hours is enable for you, it's display information on taskbar ...
Download "Rapidshare Happy Hour Checker"
If you don't want to install any tool, you can use this Firefox Add-ons: https://addons.mozilla.org/en-US/firefox/addon/7353 (Homepage: http://apusay.blogspot.com/)