JStock is a free stock market software for 23 countries. It provides Real-Time stock info, Intraday stock price snapshot, stock indicator editor, Stock indicator scanner, Portfolio management and Market chit chat features. Free SMS/email alert supported[.]
JStock boasts a pretty impressive feature list. I can see the alerts (email/text/tray) being especially useful. Additionally, it is built on Java, so it runs on any OS.
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