Custom compose sequences in X 
dusub: Subtract two 'du'-style listings 
Life is a constant war against the limited size of backup media. Here is my next weapon in the fight: dusub. Save a du listing today, then find out tomorrow or next week what's been growing: dusub olddu newdu or du … | dusub olddu Positive numbers in the output represent an item that grew since olddu; negative numbers represent a decrease in size since olddu. Version 2 knows about "du -h"-style listings. dusub is useful with sorttop: du … | dusub olddu | sorttop Files currently attached to this page: dusub-v2.py2.4kBdusub.py1.4kB
tardiff: diff two (compressed) tar files without extracting 
Recently I was googling for a script to compare tar files, and found references to a perl script (which I did not read) which reportedly did this by expanding both tar files and then diffing the trees. This would actually have been fine for my case, but some people noted that their use case involved tarfiles that were too big to extract comfortably. I assume that this is due to space considerations, but doubtless there are time considerations too.