I finally manage to install FreeBSD on my desktop, with all nasty desktop things I need (flash, skype). All good, with one exception (it exists in everything X based I think) - not all fullscreen programs manage to inhibit the screensaver, and sometimes very annoyingly xscreensaver (what I use for screensaver) blanks the screen in the middle of some movie. I got enough anger and here's little patch in result of this. What the patch does is: when time to blank the screen comes it checks if there's any window with dimensions of the screen and if there is such window - disable blanking for one minute.
For the man patch remove the [FILE].txt[/FILE] extension(the forum attach functionality doesn't seem to like it otherwise
P.S. It'll sound bit strange from me, but, for those of you interested in such a screensaver functionality: since this is my first post in the forum I'll suggest not to just apply the patch, but take a look at it yourself, or wait some more known to the community to say its safe (not malicious).