This is the forum for helping you out if you're stuck or if you want to discuss the nitty gritty details of the dungeons within Mount Grimrock. Warning: forum contains spoilers!
I was stuck on this for a while too. No matter how much I tried, I couldn't get through it fast enough. Here's how I finally managed:
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Stand right next to the button. Press the "S" key before you press the button to deactivate the teleported. Press the button just as your party starts moving away.
This thread helped me (thanks!), but here's specifically what I needed to do to get past this:
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I needed to click the mouse to press the button *and* press and hold S at the same time in order to have enough time to get past the teleport before it turned back on.
Note: I didn't notice the post above mine as it was on page 2 (which I didn't notice). It's basically the same, but I thought I'd leave mine just in case it helps someone else!
There's another way for those of you having trouble bypassing this.
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When you get near the end, you'll be north of the room on the teleporter's other side. Look for a button that'll open up the wall, letting you enter without dealing with the teleporter.