[alexhawdon]

To reiterate what others are saying, you can do web stuff without necessarily relying on a database.

Implementing computer vision techniques in Javascript seems to be quite popular at the moment and could make for a good project. You could get a lot of mileage out of exploring what techniques are feasible and which aren't and what you can do to optimise things. Depending on what your eventual application is it will likely need a user interface - make sure you back up its design with HCI theory and methodical evaluation and that will also add to your grade.