After the great feedback I've gotten from the previous post, I decided to add a tad bit more functionality... namely the ability to drag the upper and lower selected chart areas. Same link as before... just click and drag...
Yeah, this is pretty cool. The only thing missing is for it to use dynamic data (i.e. start from no data points and slowly grow in size over time) and it would be almost exactly what I need. I was looking for a simple way to do a scrollable line chart, but this is much nicer. Great work. It is nice to see people who give to the community without asking for money, I'm seeing less and less of that.
Cyril