Programming an Atmel chip using Arduino Uno

http://3g1l.com/blog-burn-bootloader-blank-atmega328atmega328p-arduino-uno

Interfacing with OV7670 camera modulle

http://embeddedprogrammer.blogspot.sg/2012/07/hacking-ov7670-camera-module-sccb-cheat.html

xbee to Arduino

http://cs.smith.edu/dftwiki/index.php/Tutorial:_Arduino_and_XBee_Communication

Infra Red code decoder using Panasonic PNA4602

check this out

http://3ngin33ringp4ysicswex.wordpress.com/2012/05/22/arduino-tv-controller/

Build up of wireless on Arduino

Tutorial to connect motors and xbee shield to Arduino
http://www.jayconsystems.com/tutorial/xbee_Shield/

http://tutorial.cytron.com.my/2013/03/29/arduino-edubot/

http://letsmakerobots.com/node/36345?page=1

Programming the Atmel /ATtiny using Arduino

Found this on Make-mag link
 programming ATtiny using Arduino board

http://hlt.media.mit.edu/?p=1706

Another Atmel
http://bytesandlogics.wordpress.com/category/arduino/

Arduino tutorial

http://www.mindkits.co.nz/tutorials

Hacking hardware - Arduino