Using Colours to Identify Non Unique Data

Hi

I thought I'd posted thsi already, but apparently not (so apologies if this appears twice)

Don't know if this is possible, but if it is it would really make a big job easier....

Is there a way that I can make Excel display a cell colour if the data in that cell is not unique to the rest of the column? IE Column A is a list of song tracks, if tracks that were listed more than once in that column were highlighted yellow it would make it easier to spot them and then edit my spreadsheet down.

Thanks in advance for any help

Mossy