http://dunkels.com/adam/contiki/

from slashdot:
		
The Contiki Desktop OS for C64, NES, 8-bit Atari, 

Posted by Hemos on Monday March 10, @08:04AM
from the making-the-jump dept.
Adam Dunkels writes "This is for those of you who think that a text-based operating system that fits compressed on a 1.44Mb floppy counts as 'tiny': the brand new Contiki operating system and desktop environment for the Commodore 64, with ports to a bunch of other platforms such as the 8-bit Nintendo Entertainment System, the VIC-20, 8-bit Ataris, Atari Jaguar, the Tandy CoCo, and the Apple ][ under development. The Contiki system includes the following: a multi-tasking kernel, a windowing system and themeable GUI toolkit, a screen saver, a TCP/IP stack, a personal web server, and a web browser. The Contiki web browser, which is likely to be the world's smallest browser given its extremely small memory footprint, is the world's first true web browser for an 8-bit system and probably makes the 21 years old Commodore 64 the oldest system ever to run a real web browser! All of the above programs are contained in a single, fully self-contained, 42 kilobytes large binary. The entire Contiki system with all programs running simultaneously is comfortable in 64 kilobytes of memory. The name 'Contiki' is derived from Thor Heyerdahl's famous Kon-Tiki raft which was able to sail across the Pacific Ocean despite being built using prehistoric techniques, something previously thought impossible. There are also screenshots and a FAQ avaliable."