I got a BB Curve about 6 months ago, downloaded (and discarded) a bazillion utilities... but among those I kept was one that I absolutely loved.
It gave a menu option to add a "star" to an email message - and that star synced with my gmail account - but sad story, when I updated the Curve to the new OS 5.0x, it wiped my applications and I cannot find it again! DOH!
I also haven't figured out how to reload just one application from a backup - I don't want to reload a whole backup.
I don't know where I downloaded it, nor from whom, nor the name. All I can tell you is that it was a free application and I think the only thing it did was add an option to the email menu for the star.