Can we generalise forced moves?

Sometimes we play a move thinking that our opponent is now forced to reply with a particular move. But to our surprise he plays some other move leaving our previous move not only not-forcing but also sometimes bad.

So can you people discuss some moves where the opponent is always forced to play a particular move or he loses material.

The only really forcing moves are with checks, or involving check-mate threats which cannot be stopped. It's the same with pins; only absolute pins are guaranteed to work:

Eh, 2...Qxd5 wins simply doesn't it? The trap you're thinking of is:

Sure, but if there wasn't anything to fall into (ie. make a mistake) it wouldn't be much of a trap, would it? :)

But of course you're right - it's at least easier to fall for your variation.