A preliminary experiment is carried out to investigate the effects of LED light animations on a user's perception of a computer. As anthropomorphism has become an important factor in interaction design, current research tends to add human-like expression abilities to interactive devices. Such methods, however, have limitations as they are complex and not applicable to many currently-in-use appearance-constrained devices such as personal computers. Thus, in this work we investigate an alternative method: expressive light. We attached a programmable RGB LED strip to the front-bottom of a monitor and developed a ping pong game for carrying out an experiment. We collected both game log and questionnaire data from participants. Our results show that participants who played the game with LED light animations liked the game more and perceived the computer as better and more humanlike. In addition, no evidence suggested a negative effect on a user's task performance or lead to additional workload.