I think a better idea would be to post 1-season wonders; a list of players who just had one really good season but did little appart from that.
Players that come to mind are:
Rainer Schuettler - year-end rank in 2003 was 6, next best year-end rank was 33
Magnus Norman - year-end rank in 2000 was 4, next best year-end rank was 15
Jonas Bjorkman - year-end rank in 1997 was 4, next best year-end rank was 24