A buddy and I were playing with Sonobus this morning. It lets you collaborate on music remotely.

Musicians will know already, but if you’re not aware, the latency (lag) between participants makes it impractical to play in time together. But if you can get it below 30ms then it’s roughly equivalent to playing with someone across the room. Needs a hard wired connection and the other people probably can’t be more than 500 miles away. But for me eliminates a two hour round trip to work on a song.