Apologies if this has been stated already, but I couldn't find where this request ties into a plugin that has been created on here...

sdmitch has a 'blog' - http://sdmitch.blogspot.com.au/

Scroll down to
Tile&Brick Maker - Interactive tool to create tile and brick pattern on face.
Thanks Sam

Your site is down, temporarily I hope?

edit - all good

http://www.openscad.org/

Nice work, I didn't even know it was possible to do this in Sketchup.

Keep in mind I don't know if its a good idea to use your computer in the shower...

Ditto