Grepping the latest file containing a string using the (-l) flag, then take the last item returned using tail -1, you can get the latest filename of a file containing any given string. When wrapped in This can be passed along to less, cat or vim to instantly read the file containing the last occurence of any given string.
Get me the last log with the string "Error" in it:
$ less $(grep "Error" -l *log | tail -1)
Get me the last log with the string "Error" and jump to the first iteration:
$ x="Error"; less -p$x $(grep $x -l *log | tail -1)
Tip: use n and N to page through occurrences. I find this much more useful than grepping alone!