During one of my recent projects I had an opportunity to try out MockingBird. I must say that - yet still a bit limited - it is a wonderful tool to mock up interfaces and try them out on regular users.
Unfortunately, I have not tried out other tools (this one sufficed) - of which I've heard of balsamiq - but it seems that this one is really worth mentioning.
Let me know if you have your own experiences with these tools!
23.04.2010 - Grzesiek has posted the list of 10 Excellent Tools for Creating Web Design Wireframes on the buzz. Thanks!
