Ok, so move up to a bigger chip - 1284P.
16K SRAM, 128K Flash, 4k EEPROM.
Also dual hardware serial, 32 IO.
Easily added to Arduino environment
http://forum.arduino.cc/index.php?topic=235521
I offer several form factors of boards, from duemilanove type card to one with SD, RTC, RS232 buffer for 2nd port, optional screw terminals, onboard or offboard USB/Serial, to a little one that is pretty barebones (DIP format coming soon too):
http://www.crossroadsfencing.com/BobuinoRev17/
