a little trap

After seeing your headsup opponent overbet the pot 4 times in row, you strongly suspect it's not for value. All you have to do then is hit a hand and show just a little weakness...

Full Tilt Poker, $20 + $2 NL Hold'em Sit n' Go, 150/300 Blinds, 2 Players
LeggoPoker.com - Hand History Converter

Hero (SB): 8,080
BB: 5,420

Pre-Flop: (450) K Q dealt to Hero (SB)
Hero calls 150, BB checks

Flop: (600) K 2 T (2 Players)
BB checks, Hero checks

Got my top pair, decent kicker. Just one check should trigger this guy's aggro-donk mode...

Turn: (600) 9 (2 Players)
BB bets 5,120 and is All-In,
Success. Now all we have to do is call and avoid draws...

Hero calls 5,120
River: (10,840) 7 (2 Players - 1 is All-In)
Results: 10,840 Pot

Hero showed K Q (a pair of Kings) and WON 10,840 (+5,420 NET)
BB showed 9 4 (a pair of Nines) and LOST (-5,420 NET)

Only had to avoid 5 outs one time - a 9-1 favorite to take the tourney.