Jase,
Personally, I'd look at the Polycom VSX7000 or the Sony PCS-1. They're reasonably priced, and you'll find that your 2MB line should be adequate to pass video traffic using the H.264 algorithm. They're both set-top systems, but I recommend that over desktop for the sheer fact that they look more professional (not to mention better video).
As far as the firewall is concerned, there are a number of options available to you. Do some research on Google for "NAT firewall traversal" and you should get a lot of answers. Ideally, though, these systems should reside outside of your firewall.
You can get pricing at:
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If you're just playing around, and dont need a enterprise class video system, look into:
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Thanks Chris
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