Trend Micro's SafeSync software sounds an awful lot like Dropbox: it automatically syncs the files of your choosing directly from your Windows or Mac computer into the cloud, and lets you access them via mobile devices or share them with others. So what are the differences?
On the upside: rather than being restricted to your standard Dropbox folder, you can share any folders or files of your choosing. You can rename pictures and other files on your mobile device (iOS or Android) before sharing. Pricing for the service is in Australian dollars, and even allowing for the strong US dollar, works out cheaper per gigabyte. A 20GB one-year subscription is $39.95, 50GB is $59.95, and 100GB is $99.95. (Dropbox charges $US99 for 50GB over a year, or $US199 for 100GB.) Trend uses its own data centres, so you won't be subject to outages from Amazon a la Dropbox (though that doesn't mean Trend might not also experience outages; they happen, people).
On the downside: there's no free version (a la Dropbox's 2GB), so you can't really try it out and see how you like it. (Subscribers to Trend's Titanium security software do get 10GB of SafeSync access, but that's not free either.) There's also not the same range of integration with other apps or as many mobile clients (you can share files through virtually any mobile browser, but that's not the same thing). More to the point, I found the Windows software more intrusive and slower than Dropbox and it crashed occasionally, as well as demanding a reboot every time it updated.
Bottom line: if you're just doing basic syncing and want as much data as possible, then SafeSync is somewhat cheaper. However, if you're keen for a free service or want access on other devices or through other apps, Dropbox is still a better bet.