Balsamiq Mockups - cool, but limited
A new prototyping tool called Balsamiq Mockups was recently launched. Have a look at this demo video…
…and then have a play with it. It’s built in Flash and borrows some core concepts from the Flash authoring tool. It’s primarily a library of common UI elements that are easy to combine and mockup a screen layout. The hand-drawn look of the widgets is useful to convey the purpose of a mockup - it’s a work in progress, not a finished design.
Unfortunately, you can only build static pages. There’s no way (at this point, that I could see) to build a simulation of a web site or application - moving thru different screens and different states. So as a prototyping tool it’s actually very limited.
This tool might be helpful to mockup a single screen, but building web sites and apps isn’t about screens, it’s about experiences.

Posting your comment
Peldi Guilizzoni | 31 July 2008 @ 8:50 pm
Hi there, thanks for the review. You are right, right now you have to design each screen/state of your application separately. The ability to link mockups together is a highly requested feature, and something I plan to add in the future.
Philip Fierlinger | 1 August 2008 @ 2:26 pm
Great to hear it, Pedli. Thanks for responding.
It will obviously be important to be able to easily control which screen elements change and which stay constant between different pages/stages.
Is that part of the plan?