1. Online threat/request referring to the practice of outlining one's residence on a Google map and uploading the picture as to pinpoint one's own location. From Nahright.com
2. The practice of actually driving around the block on which a victim's house is located in attempts to catch the person outside of the safety of their home.
1. "Yo man! Circle yo crib (house) then, i'll be on the next flight." - cOLD (Nahright)
2. "They cannot see me, they are like Stevie... I'll circle your house like BBs." - Lil Wayne, Upgrade U
In terms of speaking like a teenage in the urban rap culture (brought on supposedly by the gang Blackstreet; See diggity) Piggity is the verbword of asking for a sample of something. This prase started in southern california used by mostly fans of underground rap.
Also a slang reference to a peice or pipe
"Can i have a piggity of your _____?"
"Dawg lemme get a piggity of that diggity dankness!"