RapidShare and MegaUpload are very popular file sharing service that allow users to upload and download large files. The Free accounts have many restrictions on free accounts and do not allow you to download more than a specified limit within a time span. They have very strict checks over IP addresses so you may not bypass their download limits.
You can always buy a premium account from either of these sites and download the files unrestricted. But the rates for availing premium membership is not affordable by many, lots of users use these services to upload their files.
You can get Free RapidShare Premium accounts by signing up at freerapidshareaccount.com or freerapidaccount.com. The catch though is that you have to successfully refer 5 friends to signup using your own referral URL and also complete their offers which are mostly surveys.
Another site which offers both free Premium RapidShare as well as Premium MegaUpload accounts is freepremiumaccounts.com, premiumforfree.com also provides you with free Premium accounts. The rules are basically the same for all the sites complete offer and refer friends.
I personally have not tried out the above services, but one of my friends used to try out such services to get free phone minutes from PC to a cell phone or a land line and usually got the phone minutes when he completed a offer the site asked him to.
You can either get a free premium RapidShare account for 1 month by referring 5 friends and completing 1 offers or get a RapidShare Premium account for 3 months by referring 12 friends. If you want to get a premium account give it a try, also do let me know if it works for you.
Well a RapidShare premium account for 1 month costs around 7 euros so I assume that they may be making much more money than that when 6 users complete their survey offers.