Alias ls="ls -1 -c -t | less"
The idea is:
turn yourself into a human LRU cache for filenames. Whenever you enter a directory and ls, you see a sorted, fullscreen, scrollable list of the files you used in that dir recently, which are probably the ones you want to see again!
Breakdown:
"-c -t" sort by time last changed "-1" to ease reading "| less" so that if (output nLines) > (screen height), the first lines (best sorted results) get shown