I spotted this place a few months ago. It's right around the corner from Horace & Dickies on the north side of H Street. It's just a carryout window that serves ice cream and water ice (blueberry, cherry, pina colada, a dozen other flavors) but a Hill Rag article mentioned that they're serving cheesesteaks. The lady who runs the place gets her equipment and materials from Philadelphia, so the sub is served on Amoroso rolls. You can get them with American, Cheez Wiz, or provolone. The steak isn't the usual Steak-Ums stuff you find in DC carryouts. This is thin shaved ribeye. $4.50 for the half-sub (about 7") or $8.50 for the large (about 14"). They don't skimp on the meat either. My large held about a pound of meat. The bread is nice and soft and soaks up the juices quite nicely. Not as good as Al's in Del Ray, but I think they're better than the sub shop on 8th Street SE or South Street Steaks in College Park. Definitely cheaper and one of the best cheesesteaks I've had in DC. If you're clubbin on H Street, want a quick meal for the ride home, and the line at H&D is too long, give the Philadelphia Water Ice Factory a try. I'll be back.
PS: They also serve funnel cake, chili cheese halfsmokes, cheesefries, pizza, hoagies, and gelato. Basically, anything a drunk could possibly want at 1am.