Those zany boffins at ZURB have just unleashed their latest creation: something they call Bounce. Their website claims Bounce is a "fun and easy way to share ideas on a website" and after a quick play, I'd have to agree.
It allows you to instantly take a screenshot of a website, annotate it with feedback and share it with others to provide their comments, all without a single login or sign up form in sight.
Bounce is a lightweight and totally free (as in beer) version of their Notable app, created as a way of both spreading the word about their paid offering, as well as a "sandbox" of sorts, allowing them to test new interface ideas and features without potentially upsetting their paying customers with untested concepts.
I think this idea is brilliant. It's very similar to the way that 37signals uses their free apps, Ta-Da List and Writeboard, to promote their bread-and-butter products such as Basecamp. As a bonus, for those users that are happy to just go on using just the free app, the 37signals brand is still in the back of their minds as a generous company willing to share some of their simpler tools with the wider community.
Personally, I'll be getting getting a lot of use out of Bounce, and I'd be very interested to find out how this move pays off for ZURB in the long term.
* While I can't personally vouch for the exact level of boffinry possessed by ZURB, I'm sure they're quite bright. :)