iGOOGLE,GMAIL, CHROME themes

I use all the above three to a large extent and thus customised each of them .
I thought that those settings are " BROSWER" settings, but when i access either of them from work place , i quite don't see my settings.

For example: I have activated a Goggle labs feature" mark as read " button.From my personal computer yes this button is still enabled, but from any other computer I still need to select 'mark as read' from the drop down.

So where exactly are these settings done? and how come they are not accessible for the same user from different IP( can we say this?)