Zerocool60544 in the AutoIT forums writes about a PC control project using a browser or cell phone "I use lego mindstorms' motors, they don't a lot of torque but I geared them down to be a little slower but stronger. The water bottles are the counter weights so their is always tension on the line. There are two motors on either side. (one near the closed position and one near the open position)." [via] Link.
http://blog.makezine.com/archive/2006/01/diy_cellphone_door_opener.html