step 1: install oculo

step 2: create oculo wigdet

step 3: configure oculo widget;
website = http://www.n900wallpapers.com/random

step 4: go to the next conf screen and click the wrench icon
css selector = #mainImage

step 5: on the next conf screen, choose "use as wallpaper"

step 6: choose the suitable update time and finish the wizard

your random wallpaper should be loading now. even though the oculo widget is there on the sreen, its not visible. but it is clickable. click on the area of your desktop where the widget is suppose to be there, it will bring up the "update" button. incase you dont like the current wallpaper, update it. hope this helps.