Upgrading their ATiny2313 breakout board business card, Evil Mad Scientist Laboratories writes:
There are a couple of nice improvements for the new version. First, we made the board single sided to match our original ATmegaxx8 board– this means that it’s relatively easy to print out the layer separations and make your own at home, if you like to etch your own boards. We also changed around the configuration of the prototyping areas, making it so that you can now fit up to two DIP-8 packages, breadboard style, on the board.
As usual, it’s open source with files included to make your own at home.
Business card AVR breakout boards (for ATmetaXX8)
From the pages of MAKE: