About a month or so ago, I finished AppBackup*.
This application works on Debian deratives of Linux (incl. Mint, Ubuntu, Kubuntu, Crunchbang etc) and creates a backup of your installed applications and saves them on a Dropbox account (Only DB at the moment).
This software was created using the amazing Illumination Software Creator by Radical Breeze.
Then the end of last month Radical Breeze through together a competition for the best apps.
Low and behold, I won with AppBackup* (see http://blog.radicalbreeze.com/?p=260).

So, why don’t you checkout the application and if there is enough interest, I will post the source code which you can change freely and redistribute.

* AppBackup is not in any way associated with an iPhone product by the same name, I was unaware the name was already in use when I finished the product