Firefox extension Happy Checker checks and alerts the user when Rapidshare Happy Hours is in place. Being a Firefox extension, it is cross platform and works on Windows, Linux and Mac OS X.
Happy Hours checker Firefox addon
Happy Checker has an icon at the bottom right of Firefox, clicking on which will bring up a popup with options to check for Happy Hours. If Happy Hours is detected, Happy Checker brings up a message box like below:

What is Rapidshare Happy Hours
Rapidshare Happy Hours is the hours designated by Rapidshare during which file downloads become easier. You do not need to enter difficult image verification or wait for the download. Only a small fraction of the bandwidth used is counted towards your daily limit. You can also use download managers.
Using Raptor, a download manager for Rapidshare is also a good idea.
Get Rapidshare Happy Hours addon
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