I've been working on a breakout board to support the tiny core found here: http://code.google.com/p/arduino-tiny/
This will allow you to use Attiny85, Attiny45 and Attiny2313 from one dev board which can easily be used with breadboard. So far this is an unproven design, so if anyone wants to test it feel free to make your own boards. I'll be having some made in the near future, january probably. I have yet to write the support documentation, so any questions please ask!