Thanks again for your lovely code !
I would like to propose some improvments if possible.

1. In youtube video, it would be nice to enable fullscreen mode, as in youtube site.
I have enabled the full screen button by adding &fs=1 in the youtube link:

<a href="http://www.youtube.com/v/OkauTgC_Bjk&hl=en&fs=1" rel="floatbox" rev="width:600 height:344 scrolling:no ">

Take a look in my site : http://www.4parchitects.com/presentationspat1.htm
it is the small animated gif on the right side of the page.

2. Is it possible to disable click on the youtube video ? in order to avoid visitor from opening the youtube site and escaping from my site?

thanks !!!! and congratulations for your effort.

Turns out enabling the full screen youtube is not so difficult. I'll do some more testing with it, and add that to the next version. In the mean-time, here's how you can patch it in to v3.50 if you like.

In the floatbox/modules folder, edit mediaHTML.js.
Near the top, find:
params = { wmode:'window' ...
Insert the full-screen parameter like this
params = { allowfullscreen:'true', wmode:'window' ...

On your site, you are not using the compressed floatbox files, but if you were, or if you want to, delete the two mediaHTML files in the floatbox/compressed/modules folder, and copy mediaHTML.js from floatbox/modules to floatbox/compressed/modules.

On the anchor with the youtube href on it, make sure &amp;fs=1 is on the end of the querystring, which it already is in your case. Voila, the fullscreen button now works.

No luck on the disabling of click on the youtube vide though. Your visitors can escape.