clean back wall vs. grown over back wall

[jasontk]

I was interested in seeing some comparisons of people who clean their back glass pane and those who let it just grow over. If you have pictures of either please post!

 

[xabxam]

I let mine grow over with coralline algae,I like the natural look.I take a pic because my lights are off right now.

 

[polarpooch]

there's a pic of the back of my reef tank posted here somewhere...under "sometimes my corals amaze me".
I let it grow over, except it doesn't grow over much, since I have snails that take care of it. It's also against a wall, so it doesn't get the direct sunlight the sides get. I do clean the sides every now and again, when the coraline gets too thick, otherwise, I leave it be. I like the "natural" look, too.
However, on my eel tank, I do try to keep the back clean, because the scum is not pretty like it is in the reef.