The Linemen - A good WI phreaking group in the beginning stages.
Rancho Nevada - Multitudes of information.  A must for anyone's bookmarks. 
Phrack Magazine - No comment necessary. 
Isecure.org - Good 'sploit stuff.  Some good texts, well worth reading.  
Slashdot.org - A kickass portal.  
Phone Punx Network -  One of the few really good 'zines left.
ATTRITION - A really good site, just for kicks.. it's cool, just look.
DOC - They're just cool, look damnit. =)
DefCon - I wish i could go =\
DaemonLinux - If you ask why, it's not your bag.
HNN - yay, sellout hacker news!