The world of open source is structured to invite unusual, often downright quirky contributions from people with unusual skills, and that inevitably leads to offbeat inventions. On the Linux front, especially because of easily executed embedded Linux concepts, both hardware and software inventions of the quirky type appear regularly. Some of them are quite useful, some of them are fun, and some are both. Here are five products and inventions based on Linux that Rube Goldberg might have been envious of.

As a Mac user, I'm often disappointed at the lack of good open source software designed specifically for my operating system so I was really happy to read the news at TUAW.com that Sweet.fm is now an open source project. If you have a Mac and like to stream music from Last.fm, this is one app you need to check out.

Recently I've come to really like Pandora, the free, automated music recommendation and Internet radio service created by the Music Genome Project. If you haven't tried it, it does an uncanny job of serving up artists and songs you may not have heard of, based on similarities to artists and songs that it already knows you like. Pandora's skill at this is based on how the Music Genome Project indexes over 400 attributes of songs in its database, relying on analyses from human musicians and on algorithms. Now, Livio has a $150 Linux-based Internet radio (shown) that plays back both personalized streams from Pandora, and streams from over 11,000 other stations. Especially for those who like Pandora, this radio looks appealing.