The Illinois Railway Museum has several webcams: http://www2.irm.org/cam/index.html. You're not likely to see very much during the off-season and on weekdays, but there's always stuff to be seen when the museum's busy.
I don't know how much time that will be onlyne,but I profite of the opportunity,It's a group against CN noise in PSC yard and they put a webcam to show train,by the way,lots of Montrealer railfans watch this webcam
here the link and it's on real time http://69.70.116.242:8100/view/index.shtml
do not load the activex component it's no necessary to get it,it's only for the sound and the webcam get no sound..