Common words:
* rag (a piece of cloth)
* flag (a piece of cloth used as a symbol)
* swag (stolen goods)
* brag (to boast)
* drag (to pull something along)
Less common words:
* scrag (a thin, bony neck)
* shag (rough, matted hair)
* slag (waste matter from a furnace)
* sprag (a wedge used to prevent movement)
* trag (a type of wooden trap used to catch birds)
Words from other languages:
* darg (Australian slang for a day's work)
* drog (Irish Gaelic for a drink)
Let me know if you'd like more examples, or if you're looking for a specific type of word!