Slashdot has that with their friend-foe feature. You could assign anywhere between a +2 and -2 bonus to anyone you friended or foed. Additionally you could assi

Slashdot has that with their friend-foe feature. You could assign anywhere between a +2 and -2 bonus to anyone you friended or foed. Additionally you could assign bonuses to anyone that friended or foed you. Comments only had a score range of +5 to -2 with -2 being completely hidden. So someone you foed at -2 could only show up for you if his comment got a +3. (Default view threshold is 1.)