Are you a digital packrat, uploading anything and everything you can possibly think of to your Dropbox Pro account? Happy days are here again, friends: the storage service has upgraded its Pro accounts, doubling its 50GB and 100GB plans for the same cost (the Pro 100 is $10 per month or $100 per year, and the Pro 200 is $20 per month or $200 per year) while adding a higher-tiered 500GB option. We're still waiting to hear exactly how much the top-end storage option will cost, but Dropbox expects to publish its new pricing plans this evening.Filed under: Sto