La Blogotheque is a fabulous place to find some your favorite artists or bands--Arcade Fire, Andrew Bird, Beirut, Sufjan Stevens, etc.--playing live & unplugged in various settings (in the streets, on rooftops, in cafes and elevators) and in various towns and cities.
Here are a few of my favorite videos that are posted on the website:
Sufjan Stevens - The Lakes of Canada
Arcade Fire - Neon Bible and Wake Up
Beirut - Nantes
Andrew Bird - Spare-Oh
Cali - La Fin Du Monde