Gyazo
Gyazo is a free opensource screenshot program for Windows, Mac OS X and Linux. The program allows users to create screenshots and uploads them directly to the cloud, producing an unguessable unique URL to the screenshot.
Features
Screenshots and Animated GIFs
Gyazo has a minimal user interface consisting of a small set of options available by right clicking the taskbar icon. Launching the application displays a crosshair cursor with which the user selects the area to be uploaded. Gyazo uploads the image to their servers, and then opens a browser pointing to the unique URL for the image, which can then be shared publicly. With the release of version 2.0 Gyazo also includes the ability to select a portion of the screen for GIF capture and allows users to create animated GIF or MP4 video for up to ten seconds.
Image uploading
Gyazo also allows users to upload any image by dragging the image to the Gyazo icon.
Cloud storage
Gyazo uploads every screenshot to their servers, basically allowing free cloud storage, which Gyazo says can be used indefinitely.
Premium Accounts (Ninja)
Users can upgrade their free account to Premium for a monthly subscription fee. Premium users have access to unlimited storage and uploading, the ability to draw arrows on images, and see no advertisements.