Similar to an X Wing, look for three rows or columns where the same number only has two possible locations. 

In this example, the number 2 only has two possible locations in these columns:

The possible 2's also line up in the rows, so there are two possible locations in each row:

This means that there are only two possible ways to fill the number 2:

Both sets of possibilities mean that the number 2 must occur in one of these three columns for all intersecting rows. As a result, the number 2 can be removed as a possibility in every other cell in these rows: