Xenharmonic Wikispaces has a new equal temperaments section devoted to organising compositions and theory by individual temperaments. This is the first online attempt that I'm aware of to organise compositions in this manner. I hope this idea takes off. I think this could be a great resource for studying the repertoire of specific temperaments.
Neil Haverstick, the prolific microtonal guitarist, author and composer, was recently interviewed at Tokafi. The interview is well worth reading. It's nice to see one of the "Forgotten Greats and Unsung Heroes" (explained in the interview) get some well deserved recognition. (see also this article.)
The hang drum is a recently invented pitched percussion instrument that has been receiving a lot of attention lately. Some of them feature microtonal tunings. You can learn more about them at this page at Odd Music
How about a xenharmonic ukulele tuned to thirteen tone equal temperament and played by a thirteen year old? You can listen to it here. (I wish I had one of those.)