Here's one that seems to work but I haven't tested it much. If the True Range on Wednesday is $1.00 and it opens Thursday at, say $18.00, then buy it if the price climbs above $18.40. In other words, buy if the price climbs 40% of the previous days True Range above the open.
If it does work, all one has to do then is figure out all the little niggling details such as stops(fixed or trailing), position size, exit strategy, etc., etc., etc., and it only works during certain market conditions and for certain stocks.