Any leave-behind board for programmed processor?

I haven't seen any board like that but you could easily get 10 PCBs made for $10 on iteadStudio or Seedstudio (or on your local PCB manufacturer for a bit more). Just fire up Eagle or any other PCB layout tool and lay down a simple board, it shouldn't take more than 30 minutes.

the guy at kickstarter is a total rip off.

I totally agree about the price on that kickstarter - $10 for the board, plus parts and time... you can buy a complete Arduino Nano or Uno for about $15 on eBay (usually with free shipping) and they would be much easier to use. Of course, the idea of kickstarter is to help fund a project to get it designed and built, not really to sell items as this one seems to do (somewhat successfully for the guy by the look of it!).

If you do want to build your own, Instructables.com has a fair number of examples.

This one, for example, includes the PCB layout and takes you through all the steps of building it: http://www.instructables.com/id/DIY-Arduino-or-The-DIY-Duino/

I simpy use an Arduino Pro Mini, I desing all my projects so I can plug one in. The $18 cost of the Pro mini is a bit cheeper than the additional soldering and board layout for the ATMEGA328 and supporting componets, plus a get a power LED and an LED on pin 13 that I use for debugging or other indications. But the best part, if I or someone else fries the chip, I don't have to scrap the entire project board.

I appreciate your kind answers guys! None was spot on, so far, but I've been snooping around meanwhile and found these:

The Really Bare Bones Board (RBBB)

http://shop.moderndevice.com/products/rbbb-kit

and their empty PCB's:

http://shop.moderndevice.com/products/rbbb-pcb

BTW, I'm totally new to this all so if the above actually DON'T solve my original question please do object.

Again, thank you all!

The RBBB is a neat idea, but I don't see much of an advantage in going with the RBBB when the Arduino Nano is about the same size as the smallest of the RBBB, and likely cheaper to get to your door (assuming RBBB adds shipping fees). Plus you won't have to assemble it.

The slightly cheaper and smaller option is the Pro Mini - I see them regularly for about $11 on eBay (free shipping too).

I might be misunderstanding the requirements though - you're only just aiming for lowest possible cost, right? And I'll add "after shipping" just to be clear.

If the lowest cost happens to be the full board, is that bad?

I guess overall the lowest cost would be the chip itself (see RRRRRRRBBA on instructables), but you said board, so there's gotta be some amount of ease-of-use involved.

Did you need it pre-assembled, or at least a pre-made pcb? The DIY-duino instructable seems to be a super cheap way to go, but you have to make the pcb yourself. I've never made my own pcb, so I don't know the costs involved there.

It seems that the problem with the premade custom "bare bones" boards is that they tend to be more expensive than a complete mass-produced Arduino.

What quantities are you needing?

I'm really interested to see what other suggestions people come up with

Thought I'd post this since I just saw on the Adafruit blog earlier, it's an Arduino-compatible circuit laided out on perma-proto board:

http://electricprojects.wordpress.com/2012/05/29/standalone-arduino/

Also, one more option to consider, the Diavolino by Evil Mad Science is low-cost Arduino-compatible board at $13 (it's full size in case you ever need to use a shield in your project):

http://evilmadscience.com/productsmenu/tinykitlist/180

Again, thank you all for you wonderful suggestions. It takes a while for me to investigate them and compare/understand the stuff, but do keep them coming.

Also a note regarding that guy on kickstarter: Since that first post, I've stumebled over his name a few times and - actually - it is clear he is very much a contributor to our little Arduino society and elsewhere, see eg: http://www.instructables.com/member/randofo/ We should probably not judge him from the unfortunate comments on that kickstarter page. Among his many(!) contributions on Instructables, there are instructions for the very "Arduino Project Board": http://www.instructables.com/id/Arduino-Project-Board/?ALLSTEPS

:-)

after following and reading this thread over a period of days now, I feel that you should perhaps consider (for the future) as a goal, moving Away from Arduino per se as, A) a form factor, and B) an IDE/Abstraction layer, and take what you`re learning to Progress beyond this, and into freeform builds and Code.

I started with arduino myself, and soon (quite quickly in fact) it became Not Enough.

my 1`st step was to freeform build boards to do jobs that I wanted doing, but I was still stuck with my modified arduino board that I put a ZIF socket on to program the chips.

so I moved to FTDI serial programmed, and That worked too!

then I realised that there was No need at all for any arduino Bootloader and that code could be put directly on the chip itself!

and discovered Other chips out there just as easy to use with more Pins that aren`t Arduino.

the fact that you`re asking these sorts of questions to begin with, says to me at least that you should consider exploring alternatives, and not be Locked into ideas of Formfactor for the female SIL headers, or to the FTDI chip, or 8u2 (or whatever the new version is for the Uno?).

it`s Seriously NOT set in stone that all Must be this way or else!...

Experiment and Express yourself!

If you decide to branch out but want to stay with the Atmega chips, check out http://www.avrfreaks.net/

Good point about other chips - for small projects the MSP430 Launchpad from TI is super inexpensive - the board with everything you need to get started is $4.30 (and free shipping in N America) and it's about 50 cents for the chip, I think. https://estore.ti.com/Product3.aspx?ProductId=2031

But I find it's a lot harder to program than the Arduino is. Maybe after spending much more time with it, it will make sense

And maybe it's because the sample is set up to be super energy efficient by doing everything with interrupts.