If you only want to share files, MediaFire is a good choice (although a major constraint with free accounts is that individual files are limited to a maximum of 200MB); in addition, it makes mass-mailing easy. RapidShare's lack of file-size limits is a plus, but its distribution tools leave a bit to be desired.
My top selections? If you're looking for a service that both syncs and shares files, SugarSync is a good choice, since it doesn't have file-size constraints and does have some remarkable pro-level features. For sharing-only tools, YouSendIt's got heavy restrictions for free users and ShareFile's got no free tier at all, but both of those services have excellent professional-level features. They, along with SugarSync, are the best of the services to grow into as needed.
Serdar Yegulalp has been writing about computers and information technology for over 15 years for a variety of publications.
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