Atmel's AT89S8252 is fine and very easily available in Greece too. Parts such as AT89S8252, some PICs and most of the AVRs are easily available in Greece. But since we are talking about 8052 here, I believe it's a good choice for a SBC. I don't know about Rx2 family (either Philips or Atmel). As for SiLabs, some of you mentioned, in the past there has been a local distributor when it was Cygnal, but unfortunately not now. Of course you can buy SiLabs on-line, but it would be difficult for a newbie to solder a surface mount component. So Atmel's part looks fine.

As for features: I think that the basic that sould be on the SBC is of course the matrix keyboard, the text LCD, ADC and DAC, some LEDs, one or two 7-segments and one or two free ports to play as Prahlad mentioned, so that means that most of the peripherals have to be memory mapped. As for I2C/SPI devices maybe the ADC and DAC could be the ones or you can have I2C/SPI port expanders where you can put the 7-segments and/or the LEDs. Not that a I2C RTC is a bad idea... Also about external RAM: I believe it should be there and if someone doesn't want it, then ok...

I don't think that features such as the PS2 connector for a keyboard or the driver for a stepper motor should be there. Not that they would be bad, but if someone would like to play with them, then a space for extra components, like Paulmon development kit or all other development kits have, could do the job.

George

P.S. Don't forget connectors/pin headers for all the signals of the AT89S8252 or what would finally be there. No one mentioned this feature ;))