The Solution to Fluid Inconsistencies and Equal Height Columns (revisited). See: the blog post.

I am column 1

I am column 2

I am column 3

I am longer

I am column 4

I am column 5 with an anchor link (if you need these, disable equal height columns)

I am the longest by far so...

I am the longest by far so...

I am the longest by far so...

I am the longest by far so...

I am column 6

I am column 7 with a link

I am column 8

I am column 9

I am column 10

I am column 11

You can see through me

I am column 12