I95, I just looked up Heller’s Bakery and got this address for them:
3221 Mt Pleasant St Northwest
I’m pretty sure that they’re still in the Columbia Heights/Mt. Pleasant neighborhood. Have you ever tried any of Cakelove’s cakes, btw? Went there last Sunday and had a "buzzball" (which is somewhat like a creampuff, only 10 times better!); I really should have taken a picture before I ate it, because it was not only -huge- but delicious! Cakelove is on U Street near 15th.