In Tomb Raider I and Anniversary, you can use a hand from the statue of Midas to turn lead into gold. However, if Lara climbs on top of the hand, she will turn into gold too. The sheer unexpectedness of it all, as well as the notion that The Dev Team Thinks of Everything, will catch you completely off guard.
In Tomb Raider II, Lara is surprised by one of Bartoli's mooks, who zipwires in, tries to gun her down, and ends up crashing into the locked doors to the Temple of Xian:
In the opening cutscene when Larson and Pierre are chasing after Lara in a stolen taxi - she jumps off her scooter and ducks under a half-closed gate, which Pierre stupidly thinks is high enough to fit the car through. This exchange follows while they are still speeding towards Lara:
Larson: We ain't gonna make that gap, boss.
Pierre: We'll make it.
Larson: Ain't gonna.
Pierre:We'll make it!
Larson: What did I tell you?
Pierre:(looking as though he's about to start a major tantrum)Mon Dieu!
Later on, Pierre orders Larson to search Lara's person. Larson is a bit too enthusiastic about this task, prompting Lara to give him a hefty knee in the groin.
In Tomb Raider: Anniversary - At the end of the Peru level, Lara reaches Qualopec's tomb. When closely examinating The remains of Qualopec, one of the Atlantean guards standing next to him roars and falls down, providing an effective, if unsurprising, scare moment. It turns funny when Lara aims her guns at the (now unmoving) bodies and quickly switches between them.
In Legend at the beginning of the Ghana level, Lara is at the base of an enormous waterfall. Pulling on a rope triggers an enormous mechanism that parts the waterfall prompting Zip:
Zip: Ooooh, that's where we put the temple!
In Tomb Raider III at the end of the level Thames Wharf, Lara gets ambushed by an assassin at a bell tower with a massive bell, who tells Lara who he works for after Lara bests him. He manages to get his gun back, points it at Lara, and states that he could retire from the money his employer put on Lara's head. Prompting this response: