AVR-Chat

> Normally i would buy the cheapest and most widely available 
> one first, just for experimenting. In my case, it's the 
> ATmega8515. But for sensors, i.e. using ADC, i would 
> recommend ATmega8535 for beginners. (The AT90s8515 and the 
> ATmega version has the same price in indonesia, so buy the 
> ATmega one if possible)

Why not go for a US$20 AVR Butterfly.

See: http://www.atmel.com/dyn/products/tools_card.asp?tool_id=3146

It comes with a LCD display, several sensors, a heap of off-chip FLASH and a
bootloader with RS232 interface and is battery powered. Ideal for making a
little data logger that senses temperature & light levels and logs them in
the onboard FLASH.

Also another consideration which makes it student/DIY friendly is that it
can be programmed completely with the free AVR-GCC C compiler.

See http://www.smileymicros.com/ for a free getting started guide.

Cheers

Alex