Google Storage is one of the newest and most promising entrants into the cloud storage market. Its integration with other Google services such as Google App Engine makes it a viable threat to the current leader, Amazon S3. The service is currently in closed beta, but if you're lucky enough to snag an invite, you'll probably want a more advanced manager than Google's bare-bones Web app, which supports little more than bucket creating and file uploading. For accessing advanced features of Google Storage such as setting HTTP headers or access control levels (ACLs), Google offers the command line utility GSUtil. But unless you're a console guru, a graphical manager such as CloudBerry Explorer for Google Storage is highly preferable.
In function and appearance, CloudBerry Explorer for Google Storage is almost identical to its counterpart for S3. The program looks like a standard FTP program, allowing file transfers between a local hard drive and Google Storage, or even from one Google Storage source to another. CloudBerry Explorer supports tabs, making it easy to manage multiple folders at once. Folder syncing is another key feature, automating the often tedious process of keeping files up-to-date. CloudBerry Explorer handily allows modifiable default values for HTTP headers and ACLs, so you won't have to tweak the settings of every file uploaded. But if you do need to change the settings of individual or groups of files, they're just a right-click away. In general, CloudBerry Explorer is very full-featured, supporting all of Google Storage's capabilities, along with nice touches such as in-depth logging.
Fast, intuitive, and reliable, CloudBerry Explorer is an impressive piece of freeware. The $40 Pro version supports compression and chunking for speeding up large file transfers, and customizable encryption for security. But most developers will not rely on these features, and the free version is quite sufficient for effective management of Google Storage.