I'm a happy camper!
Sometimes it's the little things that make life better. Today I managed to properly setup my ISP and C development environment for my AT Mega 128 development board (under Linux of course). I ran a very simple blink the LED program. I properly set the fuses so the Mega128 was running off it's internal 1MHz RC (later I'll test the 16MHz XTAL), set the port for output and I toggled the bits on and off in a never ending loop. This wasn't some major success such as writing a difficult algorithm or stomping on a stack bug but rather a confidence builder that my development environment and my basic understanding of the processor are correct. I'll have to go through this for my MSP430 and AVR32 setup also. In the mean time I'll test out my JTAG interface (I did the initial test with the ISP) and then proceed to do some debugging and manual toggling of the IO bits.
This isn't the first micro-controller development environment I've worked with. I setup an 80251 development enviroment using SDCC. That worked out very well. I also have a ton of other controllers (ARM and MIPS) but they used Linux as the underlying OS. The smaller controllers, like the PIC 14 bit family (using CCS's mid-range compiler), MSP430 and AVR (using GCC), have no OS and need a bit more care and feeding. I enjoy working within these tight environments (like only 256 bytes, note the lack of a K or M!). You're in charge and you're responsible for the havoc wreaked by your mistakes. ;-)