Well, I was considering putting in a speaker as well, but I was assessing my options before going through with it. The other thing I was thinking was building a Noisy Cricket amp
http://www.beavisaudio.com/projects/NoisyCricket/ but I wanted to know my options and like the idea of plug and play better than having to deal with a separate box to carry around with it. This is a dedicated travel guitar, so I'd like to keep it simple but self contained.