I've taken my TMS 99105 (TMS 99110) breadboard project and made a PCB for it. Simple system - processor runs at 4 MHz, two pages of 32K RAM, two pages of 32K EPROM, and an RS-232 serial port to communicate with a terminal program on a PC. Runs a system monitor, Cortex BASIC and Forth. No means of saving programs, but you can maintain/edit them on the PC and download them over the serial link. On the PCB, there are take-off points for all the main signals including the demultiplexed address and data bus, if you want to expand it further.
I've got a couple of bare PCBs spare - anyone interested? £16 each plus postage to you from the UK. There are full details plus approx. cost of the components here: http://www.stuartcon..._breadboard.htm
PM me if interested.