If he's on a draw and missed he isn't going to call 1.20 or 10.00, but if he's called you all the way down with top pair and a semi-decent kicker, then how can he fold on the river to any bet?

I always over-bet the river online when I'm sure I have the best hand. Even if you get calls only half the time your still making a ton more profit.

Sometimes you'll even get more calls with big river bets as opps with small hands will think your bluffing..