[james_s_tayler]

As an aside I once found out you can replace 'sort | uniq' entirely with an obscure awk command so long as you don't require the output to be sorted. Iirc it performs twice as fast.

  cat file.txt | awk '!x[$0]++'

[omaranto]

The awk commands prints the first occurrence of each line in the order they are found in the file. I can imagine that sometimes that might be even better than sorted order.

[pnutjam]

sort has a -u option on my linux... ------ -u, --unique with -c, check for strict ordering; without -c, output only the first of an equal run