Movies with stealth scenes?

I'm wondering if anyone knows of movies that are similar to the Splinter Cell series in that they involve infiltration and sneaking. Essentially, movies with things we ignorant bastards associate with ninjas. Hell, it could include ninjas for all I care. As long as there's an emphasis on sneaking around and acrobatic movements. It surprises me how few movies seem to have this kind of thing - it's badass.

I have tried Googling this many times, but because of that POS movie Stealth, it's proven to be a difficult task.

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I hear his theme music, he's around here somewhere...