One of the most powerful tools people use everyday is Microsoft Visio to make blueprints, drawings, flowcharts, network diagrams, etc. Could this application be the online web 2.0 application to replace Visio or similar application? Now there might be a solution on the web called Gliffy.
Gliffy is a great tool that makes it easy to create, share, and collaborate on a wide range of diagrams. Gliffy is an online diagramming service that helps users communicate with a combination of shapes, text, and lines.

You will need to register to begin drawing. Once your account is established you will be asked to enter a document name. The next screen is the design space you can work with. Gliffy rely on Flash plugin which must installed in your browser.

Gliffy comes with the nice interface with true drag and drop features — just like any other locally installed applications. You can select shapes, edit text on the fly, change colors, change size and so on. The auto-line connector tools works nice when connecting objects within Gliffy workspace.

There are more than 100 objects (symbols) available in the library of shapes including networking, UML, user interface, process flow, entity-relationship, floor plans, and basic shapes. You just drag and drop from this library.

You can import a picture of your diagram into another document in a desktop or online application. Diagrams can be stored online and can also be exported in JPEG, SVG, and PNG formats.

Share and Collaborate

By specifying e-mail addresses, a user can add collaborators to their diagram. Collaboration enables others to see and edit your work by simply entering their email address.

You can also publish your diagrams as images or URL and embedded your diagrams as dynamic content within your blog or website.