CloudApp is designed to let you share files and links with others. Once it's installed, you can drag any file over the CloudApp icon and it then returns a link to the file you can send to others through IM or e-mail (or any other manner, for that matter). CloudApp installs quickly. To use CloudApp you need to set up an account, but it's free to do so (it does require an e-mail address).
CloudApp works smoothly and easily. Simply dragging a file or defining a hot key to move a file to the cloud is a simple paradigm that works. There are some configuration options that allow you to set privacy levels and set up both public and private links. CloudApp provides a Web interface so you can log in and manage your uploads as well.
We found CloudApp as simple to use as any app possibly could be. Sharing files using CloudApp is almost a no-brainer, and we ended up using it far more than any other file-sharing capability (including FTP areas) just because it was easy, fast, and transparent. If you need to make files or URLs accessible by others, CloudApp is for you.