I had written a tutorial about how to install Compiz Fusion and enable different wallpapars,snowing desktop,desktop fishbowl.
Here I will share some more cool effects such as burning,blasting,dodging,folding when minimizing and un-minimizing a window,and writing on desktop with mouse,paint fire on the screen,water wave on screen,etc.

Fist of all,install graphics driver and Compiz Fusion on your ubuntu

effects when minimizing and un-minimizing a window

Go to System->Preferences->CompizConfig Setting Manager.Select Effects in left,tick Animations and single-click to go into its configuration window.
In Effect Settings tab,tick “Random Animations For All Events”

Then navigate to Focus Animations tab,choose the only line and click Edit.Set “Focus Effect” to “Dodge” and “Duration” to “500″

Now,minimize and un-minimize a window and repeat to see effect!

Writing on desktop
Go to System->Preferences->CompizConfig Setting Manager.Select Extras in left and tick “Annotate” in right.

Now,press down Super+Alt key combination,and use your left-mouse-key to write something.
press down Super+Alt key combination(Super key is the key between left-Ctrl and left-Alt),and use right-mouse-key as eraser.
press Super+Alt+k key combination to clean up the screen.

By the way,tick “Snow” in previous picture and press Super+F3 key combination to snow on the screen.Super+F3 again to stop.
Paint fire on the screen
Go to System->Preferences->CompizConfig Setting Manager.Select Effects in left and tick “Paint fire on the screen” in right.

Now,press down Super+Shift key combination and use left-mouse-key to paint fire on the screen.
press Super+Shift+c key combination to clean up the screen.

Water wave on the screen
Go to System->Preferences->CompizConfig Setting Manager.Select Effects in left and tick “Water Effect” in right.(see the previous picture.)
Press Shift+F9 key combination to enable water wave and press this key combination again to disable.