For me: 9-9-99. It was also the first (and only) system I've ever bought at launch. And I've been in love with the white lawnmower ever since.
Ooh, Christmas 2002. Got it second-hand with Sonic Adventure, Resident Evil 2 and Tokyo Highway Challenge. A year later, it started playing up and died a short while later. Got another and am still collecting. Fav game on the system has to be Street Fighter 3 Third Strike.
LAUNCH! with Sonic Adventure and SoulCalibur... The only console I've ever purchased the day it was released.
EDIT - I didn't even read the previous posts until I wrote mine... I feel like a sad echo dissipating into the distance...
I got my first one in 2005 with Sonic Adventure. It was among the things that were lost in the robbery of my house . Replaced by a Sega Sports model purchased (interestingly enough) while on vacation when said robbery occured.
2005. I was going to get one around launch, but decided to get PS2 instead (huge mistake, terrible hardware). I would have had one sooner if SEGA never pussed out.
2010. Late adopter, but I love my DC...
I got mine in '09
early 2001, I bought it for $50 from best buy.
I got one in August 2001. At that point retailers were just starting to mark down Dreamcast inventory. After about a year I had around 60 games, which was a lot for me back then, and more games than I had for any other system. Although every system dies off eventually and gets clearanced out, Dreamcast was unique in terms of awesome deals.
early 2000 for my birthday