Atomic Books is a book and comic store in Baltimore. Their focus is mostly on "underground" stuff, so you'll see a lot of zines, weird porn/art books (like a cool Bettie Page coffee table book), and (relatively) obscure comics like Frank, by Jim Woodring, and Kaz's Underground. You'll also see books about stuff like conspiracies and The Church of the Subgenius. It's pretty much the only place in Baltimore to get stuff put out by Fantagraphics Books.
They sell mostly American comics; very little manga is available, though I have seen some old Tenchi Muyo comics, and the Akira manga, which is being put out by Dark Horse Comics.
Originally, Atomic was on Howard Street, but a couple of years back, it closed down. This made people sad. It later reopend on The Avenue (36th Street) in Hampden under new management.
Atomic often wins The City Paper's Best of Baltimore competition for best book store or best comic book store. Last year, it won best book store, but a place called Cards, Comics, and Collectibles won for best comic place.