I use for my site an iframe (I know itsn't an ideal solution).
Can the height of the iframe be variable according to its content?
try using height in percentages if that doesnt work than their is only changing it by pixels which wont change with content but i think framesets can change with content im not sure about that
Wouldn't it be possible to get the height of a div within the content of an iframe and apply it to the height of the iframe. With JS for example?
A solution to that that I found while starting out is simply frames with idenically content that changes with the page added with a "meta tag" fading tequicnice makes it infallable over high speed connections. if your making a site in Frontpage and you are skilled with Frontpage iFrames are not difficul, but be careful of liking offsite material it looks horible. also try using them with out borders.