Best opensource solution is the boilerpipe library.

Do you want to know what S&P 500 will do in the next week, month, quarter? One way to make an educated guess is to find historical periods similar to the current market environment, and examine what happened. I will call this process time series matching, but you could find a similar techniques referred as technical patterns and fractals. To get some flavor about fractals, following are two articles I read recently about fractals:

Fractals — Time by DynamicHedge
Fractals and The Importance of Time Frame Diversification by David Varadi