csvdiff
csvdiff is a perl script to compare/diff two (comma) seperated files with each other. The part that is different to standard diff is, that you'll get the number of the record where the difference occours and the field/column which is different. The separator can be set to the value you want it to, not just comma. Also you can to provide a third file which contains the columnnames in one(!) line separated by your separator. If you do so, columnnames are shown if a difference is found. I wrote csvdiff to compare two database unloadfiles, but you can use it for any kind of file which has separators.