TL;DR: Anything pertaining to plants, but emphasis on growing plants or thinking of growing plants.
I'll start. Previously I've had plants in my windowsill (namely Belladonna caucasica). Nothing new to any respectable dorm, I'm sure. However this time I want something that isn't just easy on the eyes, and not easily fatal. You heard me, I want something less toxic (well, the toxicity isn't the reason, but...yeah). Don't get me wrong, enjoying the effects of a berry every now and then isn't too bad. However I'd like something that isn't likely to land me in trouble if someone happens to wonder what my plant tastes like.
Don't ask me, people do stupid shit all the time.
Regardless, here's my ideal plant: ≤ approximately 1 meter tall, visually appealing, as well as having an obvious secondary attribute, such as a natural aroma. Both aught to be enjoyed year round, or at least regularly during the fall through spring — bonus if it's an evergreen, or effectively evergreen. Annuals aren't really what I'm looking for, either; I'd like to not have to replant every year. As a sidenote: in all fairness, the size isn't a huge deal, as I am willing to prune leaves and roots as needed.
Dianthus superbus seems to be the top candidate, but it blooms from late spring to early fall; definitely not what I'm looking for in terms of flower power.
Silene capensis fits several of these categories, but nobody as far as I can tell cares when it blooms, they only want it to get vivid dreams. While I did like how it blooms during the night, I want something that I can count on to show itself off when I would like it to most. Will continue to search for it, though.
EDIT: Found one source in half an hour total of searching, describing it as "almost ever-blooming". If it doesn't pan out, it's not a huge loss.