http://h34nug3iwqjf2376fmmzdhgqivckzemcujmarlptfqeqtq7vya47yyad.onion/2008/01/13/psmisc-a-closer-look-to-a-standard-package/index.html
Namely, these are pstree , killall , fuser and peekfd . Below follows a short description of these useful tools. While everybody certainly knows killall and probably pstree , the package also contains fuser and peekfd , which were new to me until very recently (though I hear at least fuser is an age-old tool.