Just what the DIY'er needs:

[The Dong]

Just scored a nice, Samsung colour laser printer (well, OK, it's the 
other halfs, but I get to use it) and we all know that this, along with 
some glossy magazine paper, or press 'n peel, can be used to make PCB's.
And even the screen print/overlays on the finished board as well.

Some test prints show this Laser Printer to be capable of very nice 
quality, without being too expensive (but running costs for high volume 
stuff might be, but there's always cheap toner refills).

One step further, or closer, is the discovery of this Dupont Copper Clad 
film, which can be fed directly through any laser printer and is 
incredibly flexible, yet can also be soldered directly to. I kinda knew 
this stuff was available, because these exist as replacements for ribbon 
cables and even circuits where space is tight, but thought the process 
might be terribly hard or special soldering or glue required.

http://www.instructables.com/id/DIY-Flexible-Printed-Circuits/
http://www.youtube.com/watch?v=8JWEoXa5izQ

Those trainers are not so great ;)

Not too cheap this stuff (about £3-5 an A4 sheet on ebay), and quite 
hard to source, but I can see how it could make it less than an hour 
from concept and printout to populated PCB for projects. Esp surface 
mount stuff. Through hole would need a further process to epoxy it onto 
a board of some sort.