Maemo

Internet Tablet Devices : http://tablets-dev.nokia.com/

IT OS Sources for Nokia N810, N800, N770
Maemo 4.0 chinook SDK

Maemo 4.0 : http://maemo.org/development/documentation/how-tos/4-x/maemo_architecture.html
SDK : http://maemo.org/development/sdks/
Tools : http://maemo.org/development/tools/