This worked for me -- your mileage may vary, but I highly recommend it, especially if the Fedora Project is paying your travel costs! :)
From Logan Airport, get on Bus 22. Get off at the Blue Line entrance for the T -- this will likely be the stop where *everyone* gets off the bus.
Buy a Charlie Card -- put either $5 or $10 on it, since you can use it to get to Boston University on Saturday also.
Take the Blue Line to Government Center. Get off at Government Center. Look at the map, and see how the Green Line is laid out. Get on one of the trains that goes in the direction of the Hynes Convention Center -- the stop that you want, helpfully, is called Hynes.
When you get off, take the exit toward Massachusettes Avenue. Step outside. Look around. You should see the Sheraton and the Hilton hotels. Walk towards them. This involves going to Boylston and making a left, then making a right on Dalton. Only about a 5 minute walk.
The entire trip from the airport was probably 30 minutes or so, and very cheap. Do this!