Famitracker, too, is my preferred medium by which I create chiptunes. I have some non-pony stuff up at my other youtube:
http://www.youtube.com/watch?v=sUzkprKow4U The reason I prefer Famitracker is because it's tirelessly true to the source hardware from the sound standpoint. IMHO, vsts provide too much flexibility in a lot of cases while Famitracker is precisely true to vintage specs.
LSDJ is also pretty cool, and cheap as hell too. If you must use a VST, I'm a big fan of Tweakbench's work, and I find his plugins are really versatile and minimalist.
Anyway, I haven't been working with anywhere as much 8-bit stuff as I once did (Almost exclusively), but arranging for a reduced number of voices/timbres is a good thing for ANY musician to know, and I keep those ideas in mind for almost all of the music I compose.
EDIT: Almost forgot the Atari Synthcart! Technically not 8-bit (2 BIT D:) but if you hook it up to a TV, it's fun as hell for a noisy/glitchy jam.
http://www.youtube.com/watch?v=zgDyOSDUAx0 Check this mess.
"Had you played some free jazz to ninety five per cent of the people who had made 'Take Five' a smash, they would have run for cover behind the latest release by Pat Boone." - The Timelords