First, get to MIT [1].

Here's a campus map [2], with Building 66 highlighted (the parking lot is the beige rectangle next to the building).

We usually meet in room 168; if you enter at the "point" on Ames St, it is the first classroom on the left.

Note that the parking lot entrance is on Main St.  The lot is free and open to the public on weekends.

Please remember that our traditional parking lot behind building 66 is now a large construction site.

The next closest MIT parking lot that you can easily park is probably the Hayward St. Lot.

http://whereis.mit.edu/map-jpg?selection=P5&Parking=go [3]

It's near the corner of Main St, and Hayward St. (at this point Main St. is essentially one-way east bound (towards Boston)).

You can follow the directions for the traditional parking lot, but continue on Main St. and drive past the Kendall Square T station, and then turn right onto Hayward St. (It's the second right after the traffic light at Ames St.)

If you're coming from I-93, I think the best way to get to the lot is to take the hard right turn onto Memorial Drive as soon as you finish crossing on the Longfellow Bridge. Once you're on Memorial Drive take the first right (Wadsworth St.) and then turn left onto Amherst St and right onto Hayward St. The lot is on your left.

If you're heading east bound (towards Boston) on Memorial Drive, I think there's a break in the meidan strip with a sign that says "Kendall Square", that's the turn for Wadsworth St.