My current notebook (paper not computer type) is one of these:

and my coffee mug coaster is one of these:

The company uses fully etched / resist / screenprinted but unpopulated PCBs which are CNC routed into whatever shape they need. Great idea!
For those in the UK this is their site
http://www.cutouts.net/ They are based near Huddersfield (I have no connection with them whatsoever). Im sure local alternatives will be available.
Mike