Compare details of top cloud storage solutions (MoneyWatch) COMMENTARY Someday, you'll be able to tell your kids about the great cloud storage explosion of 2012 -- the year that Google Drive launched, Dropbox made major upgrades, Microsoft rolled out a totally revamped and competitive SkyDrive, and everyone finally felt comfortable storing their files online. In recent weeks I've spent a little time comparing competing cloud solutions and discussing their respective terms of service. Today you can directly compare the cost per gigabyte of each of the major alternatives. Ars technica has published a pair of charts which show which platforms (Windows, Mac, iPhone, Android, and so on) each of the major cloud services runs on. For platform compatibility, two services are neck and neck. SkyDrive is green across the board except for Linux; Dropbox works with everyone except Windows Phone. Google Drive, iCloud, and SugarSync work with most platforms, while Box brigs up the rear with more red than green (it only offers client apps for mobile devices, not the desktop). When it comes to storage prices, things get even more interesting. On price alone, Box is the clear winner, costing around 3 cents per GB across the various plans (100-300). SkyDrive is a close second at about 4 cents per GB. And Dropbox is the most expensive, clocking in at 20 cents per GB.Of course, all of those services give away several gigabytes of storage for free, so it's possible to get value from any of them without spending any money at all. There's a lot of excellent information at ars technica -- check out the complete story and see the charts for yourself.