Well, we ended up at Christopher's last night in Porter Square, Cambridge. I hadn't been there in a year or so; I forgot how good the burgers were there. They use all-natural beef that doesn't have any of the bad hormones or steroids that most other beef does. I had the English Burger, which is seasoned lightly and comes on an English muffin.
As good as the burger was, the fries were incredible! Small wedges (much smaller than O'Sullivan's) with spices added. Also, the butternut squash soup was very good, though it came in a huge place and filled me up a bit too much before my meal.
All in all, Christopher's is a decent option for those who like burgers and comfort food. Great beer selection, too!