Extract All Unique Values

Hey,
I did this a few months ago, but I don't have access to the code. In other words, I simply know it's feasible, not how to do it anymore.

Look at: Column C
Extract one of each unique value
Have each of those unique values become a "header" (they just need to go in row 1) in Sheet2

Whatever happens, this cannot alter the original data set that we're extracting from. Any ideas?

If you're just looking for a quick manual solution you could do this:

Select the data in Column C and copy it
Paste it in A2 of Sheet 2
On the ribbon select Data - Remove Duplicates
After removing the duplicates copy the unique vales
Select A1 and do Paste Special - Transpose
Now delete the values from A2 down