from Paul Graham | by Paul Graham

If you're an ambitious engineering student and you're wondering what to work on to advance your career, you're asking the wrong question. Work on whatever you're most excited about; if you're ambitious, your excitement will outweigh the hotness of the field you choose.

This is a somewhat self-correcting answer, because ambitious engineering students naturally tend to be attracted to promising fields. In fact, it's hard to imagine a better way to predict which fields are promising.