it's cool when these work

I don't try this too often, but here's a spot where I think decent players will fold their top pair pretty much always:

Full Tilt No-Limit Hold'em, $1.00 BB (2 handed) - Full-Tilt Converter Tool from FlopTurnRiver.com

Hero (Button) ($100)
SB ($104.50)

Preflop: Hero is Button with J, 4

Hero raises to $3, SB calls $2

Flop: ($6) Q, 2, 9 (2 players)

SB checks, Hero bets $4, SB raises to $14, Hero calls $10

Turn: ($34) 9 (2 players)

SB bets $15, Hero calls $15

River: ($64) A (2 players)

SB bets $20, Hero raises to $68 (All-In), 1 fold

Total pot: $104 | Rake: $0.50

Results:

Hero didn't show J, 4 (nothing).

Outcome: Hero won $103.50


Most obvious thing for me to have is an A-high flush draw, which now beats his Q. Repping a 9 here is questionable because I didn't raise the turn. A more convincing line by me could even have been raising the turn and shoving the river.