1993 ProTracker
1995 FastTracker 2 (later, with Cool Edit Pro)
2002 Modplug Tracker
2005 Renoise
2007 Renoise Registered 
Dabbled in Acid Pro, FL Studio, Cakewalk.
FT2 for a long time. I use Renoise from the very beginning (2002) 
I’ve mainly used trackers since I’ve started producing music. In the days of Amiga I was strongly stuck to OctaMED, some rare times ProTracker. Nowadays I may use numbers of software related to music production but my mainly used tool is the beloved Renoise.
I used Trackers at the very beginning of my adventure…
I stopped trusting my instincts and moved to the clumsy and awkward world of recording sequencers to make programmed music. I did this for a good few years, but was never truly happy.
Then Renoise found me and I was once again happy.
I honestly think that it has made me a better more happy person. Making music is my artful expression and I have finally freed it from commercialized products designed for other people…
I love it.
Best software I have ever used.
Iwould have a hard time answering the poll because I would be clicking a lot of the buttons… I started originally with programming sounds in Basic on my tandy 1000 (3 voice+pcm chip) but that was aeons ago 
… then switched to midi sequencing software, then music notation software for scoring… after getting extremely tired of traditional note based/midi composition trackers were such a godsend…
my first and most beloved tracker was Impulse Tracker and i used a combination of it with Cool Edit, and Sonar 1 (for effects, sequencing, editing and production) for several years… Also Logic and Pro Tools for a couple years (still use pro tools of course, but i #!@$ing hate logic 
) Current setup is mainly a mix of Renoise, Wavelab, and modular software (synthedit, bidule, max.msp from time to time). Different tools for different things .
I had to answer the first question with what I started with on the computer, Impulse Tracker, however I did move into Orion for a while (and still like it, except lately, it’s audio has started to sound…eh…‘less-clear’ compared to ReNoise…) got very adept at the concept of ‘virtual studio’-isms through it, stopping by Buzz on the way there.
I’m still waiting for the perfect app that fits my 'app’etite (sorry, couldn’t resist)…and now I’m finding myself even more cornered, having started migrating to linux…ReNoise seriously is the ONLY reason windows still remains on my computer. 
Started with Protracker, then FL Studio (it was called Fruityloops back then), then Renoise.
I do not consider FL Studio being one of the mainstream “DAWs” though. It’s something inbetween Renoise and the so called “DAWS”. FL users are looked down upon all the major “DAW” users, just for the record. 
[just like any other software composing tool is looked down upon from the tracker crowd, but I think I really should not mention that in here should I? ^^ ]
I’m using both. Always jumping back & forth between them depending on what I want to do and my current mood. Sometimes They even run in paralell combined via MIDI sync and MIDIyoke OR with FL as a VSTi inside Renoise. It’s always nice having options.
i started in impulse tracker.
messed around with modplug for a bit after i upgraded to windows 2000.
settled on fruity loops in 2003. hated it, and wrote very few songs until i discovered renoise in 2005.
Scream Tracker with crappy windows sound editor.
then Impulse Tracker with Soundforge and occasional forays into NTrack and Cubase
then Renoise and Soundforge
now Renoise and Bias Peak
I was using MOdplug then Buzz after it Modplug, next Reason. Then I came back to buzz. Now I’m using both buzz and renoise.
well, ft and samplitude, but i votet -> didnt used other DAW , smart eh ?
It started with Protracker on Amiga, then there was Octamed (Amiga) but still only 4CHN-MOD. On PC I started with Modedit, switched to X-Tracker and then to FT2.
When XP was “standard” I turned my eyes to buzz (never released a song with that) and then to Modplug.
Then there was renoise…
I didn’t find FT2, it found me in 1996. Loved it to bits, but missed the fx both IT, Modplug Tracker and MT2 could give, but didn’t feel comfortable in those softs. Tried Fruity before it was usable too, did one track. Tried Buzz, but felt it was way too cumbersome. Tried SO hard to use Psycle, loved the ideas but when Renoise found me in 2001 I was sold, and so was the software.
~ 1996 - FT2
~ 2000 - MT2 & BT2 (BushTracker, which is an awesome tracker for the AWE32)
~ 2003 - Renoise
I started with Impulse Tracker around 2001, moved to Buzz in 2003 and found Renoise in 2004.
My father was fiddling around with ModEdit (an Amiga substitute tracker for PC) in the early 90’s and about '92 I started too, no real music came from that, though. I was more playing around with it and listening to other .mods.
a year after I had Scream Tracker 3 and that’s a whole different story, a great program and I started making some real music with it.
In '96 it was Impulse Tracker until I moved to midi in 2000, a short stint with Cubase and then Logic for a few years.
I tried many other DAWs and programs and I wished for a long time for something which will let the “inspiration” flowing like a tracker. I discovered Renoise just lately- and I can’t figure out why. I just love it. It’s a great program, the best tool I have and it can become even greater in the future.
1993-1997 - ProTracker (AMIGA)
1997-1999 - Digibooster Pro, OctaMED (AMIGA)
1999-2003 - Camouflage (AMIGA)
2003-2099 - Renoise (PC)
Protracker and then Miditracker on the Amiga.
Btw I miss Protracker in the tracker-options!
Amiga trackers => Fast Tracker 2 => ModPlug (I voted other) => Renoise and Ableton when I started getting serious and wanted a live performance tool.