HALP! New Englanders!

My business Partner, the MAD SCIENTIST, has to give a presentation at Nanotech 2008 at the Hynes Convention Center in Boston, June 1-4th. It's IMPOSSIBLE to find a reasonable priced hotel online (apparently). Do any locals, or frequent travelers to Boston have any recommendations for moderate priced accommodations either near the center or easy access to the convention center by Mass transit? Unlike New York, I have almost *NO* experience with Boston proper.

Advice is oh so graciously accepted!