Google has officially announced Google Drive, which comes with 5GB of free storage. This is higher than the 2GB free storage that Dropbox offers. Additional storage on Google Drive costs $4.99 per month for 20GB and $49.99 per month for 1TB. Box.net charges $240 per year for 50GB of storage, Microsoft SkyDrive charges $50 per year for 100GB, and Dropbox charges $100 per year for 50GB. Gmail is also now offering 10GB of free storage, which will be rolled out in the next 24 hours.