Both my USB guitar input and electronic drum set have headphone jacks on them, and no way to get actual audio out of them without plugging into that. If I'm using headphones by myself that's fine, but if I want to be showing someone else while hearing what I'm doing, it's a bit of a problem!
I looked into Bluetooth speakers that have 3.5mm jacks as well (we've got a little Bluetooth speaker that I use to listen to music from my phone when I'm out in the back room doing my painting and it does okay, but the sound quality's not great plus it lacks any way of getting audio to it except Bluetooth), and decided to get the Audioengine B2. It arrived today and is both very handsome and sounds quite good!