[dasmoth]

Definitely try some different things and see what you like, but if you're looking for mission and impact I wouldn't completely dismiss web development. The web browser is a stupendously powerful tool for "getting things in front of people", and the combination of that plus some understanding of another area can achieve a lot. There could be opportunities to branch into scientific computing, fairly complex distributed systems, and more. Pretty much every area of computing except maybe hard-core embedded systems have a web component nowadays (and the "softer" end of the embedded market could have some good opportunities... can you imagine a consumer router with an actually-nice management interface? That's primarily a web-development problem!)