I remember a neat statusbar clock for the N800 and N810 that had a bigger size than the standard one just by using slots for two programs for the numbers.

Before posting my original query I spent a long time looking at Matan's modified desktop but how to easily make these changes just hasn't sunk in yet.

I'll look at Nikolai's suggestion. I already use his desktop-switcher with my own icons replacing his numbers. I think Matan's modified desktop and nine windows and desktop-switcher are quite indispensible.