I give you the BASIC Stamp[1] a BASIC environment on a chip with 25 BYTES of RAM. And the SPI RAM chip[2] (8 megabytes off a SPI port).
I built a simple PDP-11/20 emulator (not cycle accurate) that used the Atmega chip and a couple of FRAMs for 'core'. At 16MHz it ran faster than the PDP-11/20 did when it was built, and the 11/20 ran RT-11.
Basically this is a detailed way of saying that perhaps you perceive limitations where I see opportunities :-)