You mean remember the last listing of
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At the end of the generated listing's url is the string which enables you to always recreate that search. E.g.:
http://www.linuxquestions.org/questi...earchid=748796
The searchid=748796 bit means that whenever I follow the SNP link and get a list, I can change the number on the end, hit return, and effectively search as though I hadnt been here since whenever that searchid was generated. The list is now all those since that day.
Basically, write down the little number occasionally, change the number when you want to roll back the days, and hit return.