Every Thursday the local band "Naked Blue" plays at J.J.'s and from what Glen claims, they're pretty good. But then again, that could just be due to his infatuation with the lead singer.
Just a warning, since the Hampton House is both an apartment building and an office building. This means that unless you want to end up like Greg on your average NY Pub Night, you will need to sign the guest registry at the front door to make sure that your car is not towed.
-- Your Pubnight Gang of Four
Parking addendum: It's not necessary to sign in at the front desk if you are arriving after 7 or 8pm. The parking lot next to the building is available in the evening hours. Just park there and make sure you don't leave it there over night and there's no hassle. Also if you're lucky, there's parking in front of the building by the restaurant as well as on Joppa road after 7pm I believe.