How do you feel about making your own circuit boards? If you are comfortable with this, you could throw together a pretty decent board for little money.
Also, what kind of features are you looking for? ADC, PWM, UART, USB / Serial? I could design a board for you if you wished. If you need only a board with a voltage regulator and UART, go with one of the Olimex boards. If you need servo connections or LEDs / Screen, then think about designing your own board.