Charles River Museum of Industry and Innovation:
Best. Place. Ever.
Not only do they have monthly Steampunk meet-ups, they are offering a class to make your own Steampunk clock. I am all over this. Not only do you get an awesome clock, you get to learn how to manipulate gears and such to make something awesome.
Every Fall, there is a Steampunk Form & Function Exhibit that exhibits modded and Steampunk gadgetry from artwork, to working motorcycles. It is worth the $7 to visit. Unfortunately the last exhibit ended in February, so you might have to wait to suck up all that awesomeness. But starting in August 2012, they are accepting applications for the exhibit.
And the second annual International Steampunk City will take Place May12 and 13th in Waltham, MA. I went last year and it was amazing.
Not surprisingly, this will be our wedding venue.