Parking near MIT
Metered street parking in many cases is your best choice -- check the map of on-street parking meters. The meters in the area around campus are free after 8 PM and anytime on Sundays. When they are not free, though, they are limited to two hours of parking; after two hours of paid parking, you must move your car to a different zone (posted on the signs or on the map linked above). The meters are about $1.25 an hour, and can be paid with quarters or online with Passport Parking.
There is also non-metered parking on the north side of Memorial Drive, but it tends to be pretty full. Before 6 PM, it is limited to 30 minutes.
If the free options are unavailable (such as during the day on weekdays or Saturdays), and you need to park for an extended amount of time, you can park in the Albany St. Garage. The fee is $9, payable by credit/debit card only. (This rate is not available before 2:30 PM on MIT business days.)
If you are an MIT alum or otherwise eligible for an MIT parking permit, check out the Occasional/Evening parking permit from MIT's parking office, which will allow you to park in any MIT lot in evenings and anytime on weekends, such as the Kresge lot or the Mass Ave lot. In general, evenings start at 2:30 PM, but the Mass Ave lot starts at 4:30 PM.