The area around Bucharest's railway station, Gara de Nord, was until very recently something of a no-go area, particularly at night. While it remains edgy, the area (like the station itself) has had something of a clean-up and facelift of late and is at least not as threatening as before. You will still find more chancers, con-men and agressive beggars here than anywhere else in the city, while you should also keep an eye out for pickpockets and rip-off taxi drivers.
There are a couple of decent, cheap hotels in the area now: the Ibis and the Hello, and these are very much the reason that the area is more welcoming than before.
Gara de Nord
City Essentials