I looked at those links and tried your search text, and there are several nice options out there (some nicer than others).
The frustrating bit is they all seem to have a flaw of some kind, in particular they never seem to handle when you select text in the popup window, and the whole page gets blue highlight everywhere, and it looks plain ugly - I hate that. This bubbles one doesn't seem to have that problem - not sure how they are doing it. Makes it feel more solid. Plus they seem to make it pretty easy to incorporate into a webpage too (am definitely not an expert with jQuery and stuff).
Think I'm still leaning towards giving them a try.
Anybody else actually used them before though?