Download: Unique.exe 1.0
Unique.exe is a small .Net utility that I wrote to dump only the unique lines of a text file. I found this useful when combining a few lists of user names and needed to retrieve only the unique ones. It additionally sorts the lines (forward and reverse) and outputs to stdout or a file.
I haven’t done any performance tuning (it’s 143 lines long) but I would expect it to work reasonably quickly with all but very large files. (Source and release exe included.)