Something I've been looking at recently is backing a number of horses in races where a lot of horses are resuming (i.e 1st or 2nd up). My rationale is that these races are unpredictable and hence throw up many long priced winners. For the purposes of my research I looked at fields of 13+ with 5+ horses first/2nd up. In the short time that I've looked at this it has thrown up some remarkable winners in my top 6.
Most recent good results have been Umanoolla ($71 NSW) and French Revolution ($58) both on the same day at Adelaide (not a bad double return for a $36 outlay). Other good winners in the last 12 months have included Crystal Finale ($38), Fighting Harada ($70 +). THere have been many races where the stake was returned (i.e. a small amount + or -) Needless to say all of this is in retrospect and I didn't have the money on.
For anyone interested there is one bettable race today, Adelaide race 7 which I have rated 12, 14, 2, 3, 9, 16.