5. Share files without wires with Dropbox
Forget those cumbersome email attachments: With the right app, you can share files with anyone, sans the hassle.
Dropbox offers an Android app that'll bring Web-based file sharing right into your phone. You can upload and download files directly from private directories, public directories, or folders you selectively share with specific users. (Box.net offers a similar app and service.)
The coolest thing about the Dropbox app is that it fully integrates the file-sharing experience into Android. When viewing a photo on your phone, for example, you can select the system's Share option and find a command to send the image directly to your Dropbox folder.
The service provides PC-based access, too, as well as access on other smartphone platforms. Dropbox comes with 2GB of storage for free; you can opt to buy extra memory for a set monthly fee that varies based on the amount of space you choose. The client app is free.