I just bought the Elmscan 5 USB from scantool.net and got the Digimoto software.
I've found things I liked - and things I hated in all of the software packages I've tried so far - but digi is pretty good
The thing I don't like about Digimoto is that it doesn't read the absolute throttle position correctly (but other software packages I've tried do) and that it doesn't appear to read very many of the available (and unavailable) sensors. Maybe they just left off the sensors that aren't common - but the free software that comes with the tool has like 80 things it can read (most of them come back as unavailable - but at least they are there))
What I DO like is that it's got a page where you can see several of the more pertinent sensor readings in analog gauge form...
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