Yep, I recently got a daylight lamp for this very purpose. I point it at my face for 3-4 hours a day, and it improved my concentration a lot. Sometimes (esp. when working on a sleep deficit) the light makes me a bit tired.

Fun fact: When I turn on this lamp it makes me want to tidy up the room, after about 2 minutes. I suspect that's an effect also observed in anti-depressants.