Well, its kind of a combination of technical indicators, experience in looking at charts for years and knowing what patterns are just about to "go", combined with some intangibles like doing a quick test search on the ihub/Si sites for the ticker and seeing how many posts have been made on that particular ticker recently, Whether there has been news that day, if an S-8 is ending, if there is a forward looking event, etc... It's certainly not "real time" by any means but I'll come up with a dozen or so and put them in my watchlist in markettrader, and just watch them for volume,news, trading patterns during the next day(s)
for the initial screenings I just use clearstations nice little tag & Bag feature http://clearstation.etrade.com/cgi-bin/events?Cmd=techev I have had most success looking at the unusual volume tickers and the ones that it picks up around the 50 day moving averages. I like to look for ones that have enough average liquidity so entry and exit isn't too dificult.
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