I don't know where i heard it, but i believe that the average winning hand in NL Texas Hold'em is two pair. This means then that, on average, one pair is not going to be a winning hand. So how should you play your one pair type hands? I prefer to use them as bluff catchers if i am IP, particularly when there the flop contains a draw (i.e. a flush draw).

I do this because i do not want to get c/r bluffed off of my hand on the turn, nor do i want to play a big pot with just one pair. Finally, i am comfortable folding my pair of kings if a 3rd spade came in on the river and my opponent made a big bet. In order for this to work, you must know that your opponent is aggressive.

FullTiltPoker Game #2074064443: Table Brush - $0.50/$1

Seat 2(Button) Hero: ($102.45)
Seat 9 Villain: ($73.95)
7 other players, their stacks irrelevant

*** HOLE CARDS ***
Dealt to Vi-Zer0Skill [Qh Kc]
4 folds
Villain: calls $1
1 fold
Hero: raises to $5
2 folds
Villain: calls $4
*** FLOP *** [Ks 2s 8h]
Villain: checks
Hero: bets $6.60
Villain: calls $6.60
*** TURN *** [Ks 2s 8h] [6c]
Villain: checks
Hero: checks
*** RIVER *** [Ks 2s 8h 6c] [2c]
Villain: bets $22
Hero: calls $22
*** SHOW DOWN ***
Villain shows [Qs Ah] (a pair of Twos)
Hero shows [Qh Kc] (two pair, Kings and Twos)
Hero wins the pot ($65.70) with two pair, Kings and Twos