Well, i guess this is nothing new for some members here but for computers too old and slow for youtube videos (Durons and early pentiuns 4 and most of the pentiuns 3), a youtube to vlc plugin for firefox or chrome works like wonders!
https://addons.mozilla.org/en-US/firefox/addo … utube-shortcut/ (firefox)
You only need to have vlc installed (obviously) and then right click the youtube video you want to watch and click "Play video from link". I was able to play most youtube videos quite well on old slugish computers, as long yo don't have anything else eating your cpu in background up to 100%.
As for youtube on a 486, even 2 fps is quite optimistic, and i'm talking about this "youtube to vlc" solution. I don't even want to think what a flash video would do to the poor 486.